diff --git a/caravel/LICENSE b/caravel/LICENSE
new file mode 100644
index 0000000..d645695
--- /dev/null
+++ b/caravel/LICENSE
@@ -0,0 +1,202 @@
+
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diff --git a/caravel/Makefile b/caravel/Makefile
new file mode 100644
index 0000000..367d669
--- /dev/null
+++ b/caravel/Makefile
@@ -0,0 +1,506 @@
+# SPDX-FileCopyrightText: 2020 Efabless Corporation
+#
+# Licensed under the Apache License, Version 2.0 (the "License");
+# you may not use this file except in compliance with the License.
+# You may obtain a copy of the License at
+#
+#      http://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing, software
+# distributed under the License is distributed on an "AS IS" BASIS,
+# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+# See the License for the specific language governing permissions and
+# limitations under the License.
+#
+# SPDX-License-Identifier: Apache-2.0
+
+# cannot commit files larger than 100 MB to GitHub
+FILE_SIZE_LIMIT_MB = 100
+
+# Commands to be used to compress/uncompress files
+# they must operate **in place** (otherwise, modify the target to delete the
+# intermediate file/archive)
+COMPRESS ?= gzip -n --best
+UNCOMPRESS ?= gzip -d
+ARCHIVE_EXT ?= gz
+
+# The following variables are to build static pattern rules
+
+# Needed to rebuild archives that were previously split
+SPLIT_FILES := $(shell find . -type f -name "*.$(ARCHIVE_EXT).00.split")
+SPLIT_FILES_SOURCES := $(basename $(basename $(basename $(SPLIT_FILES))))
+
+# Needed to uncompress the existing archives
+ARCHIVES := $(shell find . -type f -name "*.$(ARCHIVE_EXT)")
+ARCHIVE_SOURCES := $(basename $(ARCHIVES))
+
+# Needed to compress and split files/archives that are too large
+LARGE_FILES := $(shell find ./gds -type f -name "*.gds")
+LARGE_FILES += $(shell find . -type f -size +$(FILE_SIZE_LIMIT_MB)M -not -path "./.git/*" -not -path "./gds/*" -not -path "./openlane/*")
+LARGE_FILES_GZ := $(addsuffix .$(ARCHIVE_EXT), $(LARGE_FILES))
+LARGE_FILES_GZ_SPLIT := $(addsuffix .$(ARCHIVE_EXT).00.split, $(LARGE_FILES))
+# consider splitting existing archives
+LARGE_FILES_GZ_SPLIT += $(addsuffix .00.split, $(ARCHIVES))
+
+# Caravel Root (Default: pwd)
+# Need to be overwritten if running the makefile from UPRJ_ROOT,
+# If caravel is sub-moduled in the user project, run export CARAVEL_ROOT=$(pwd)/caravel
+CARAVEL_ROOT ?= $(shell pwd)
+
+# User project root
+UPRJ_ROOT ?= $(shell pwd)
+
+# Build tasks such as make ship, make generate_fill, make set_user_id, make final run in the foreground (1) or background (0)
+FOREGROUND ?= 1
+
+# PDK setup configs
+THREADS ?= $(shell nproc)
+STD_CELL_LIBRARY ?= sky130_fd_sc_hd
+SPECIAL_VOLTAGE_LIBRARY ?= sky130_fd_sc_hvl
+IO_LIBRARY ?= sky130_fd_io
+PRIMITIVES_LIBRARY ?= sky130_fd_pr
+SKYWATER_COMMIT ?= bb2f842ac8d1b750677ca25bc71fb312859edb82
+OPEN_PDKS_COMMIT ?= b06f0f2148abd1b4f8ef60999f9991775cd87a7e
+INSTALL_SRAM ?= disabled
+
+.DEFAULT_GOAL := ship
+# We need portable GDS_FILE pointers...
+.PHONY: ship
+ship: check-env uncompress
+ifeq ($(FOREGROUND),1)
+	@echo "Running make ship in the foreground..."
+	$(MAKE) __ship
+	@echo "Make ship completed." 2>&1 | tee -a ./signoff/build/make_ship.out
+else
+	@echo "Running make ship in the background..."
+	nohup $(MAKE) __ship >/dev/null 2>&1 &
+	tail -f signoff/build/make_ship.out
+	@echo "Make ship completed."  2>&1 | tee -a ./signoff/build/make_ship.out
+endif
+
+__ship:
+	@echo "###############################################"
+	@echo "Generating Caravel GDS (sources are in the 'gds' directory)"
+	@sleep 1
+#### Runs from the CARAVEL_ROOT mag directory 
+	@echo "\
+		random seed `$(CARAVEL_ROOT)/scripts/set_user_id.py -report`; \
+		gds readonly true; \
+		gds rescale false; \
+		gds read $(UPRJ_ROOT)/gds/user_project_wrapper.gds; \
+		load caravel -dereference;\
+		select top cell;\
+		gds write $(UPRJ_ROOT)/gds/caravel.gds; \
+		exit;" > $(CARAVEL_ROOT)/mag/mag2gds_caravel.tcl
+### Runs from UPRJ_ROOT
+	@mkdir -p ./signoff/build
+	@cd $(CARAVEL_ROOT)/mag && PDKPATH=${PDK_ROOT}/sky130A magic -noc -dnull mag2gds_caravel.tcl 2>&1 | tee $(UPRJ_ROOT)/signoff/build/make_ship.out
+	@rm $(CARAVEL_ROOT)/mag/mag2gds_caravel.tcl
+
+.PHONY: clean
+clean:
+	cd $(CARAVEL_ROOT)/verilog/dv/caravel/mgmt_soc/ && \
+		$(MAKE) -j$(THREADS) clean
+	cd $(CARAVEL_ROOT)/verilog/dv/wb_utests/ && \
+		$(MAKE) -j$(THREADS) clean
+
+
+.PHONY: verify
+verify:
+	cd $(CARAVEL_ROOT)/verilog/dv/caravel/mgmt_soc/ && \
+		$(MAKE) -j$(THREADS) all
+	cd $(CARAVEL_ROOT)/verilog/dv/wb_utests/ && \
+		$(MAKE) -j$(THREADS) all
+
+
+
+#####
+$(LARGE_FILES_GZ): %.$(ARCHIVE_EXT): %
+	@if ! [ $(suffix $<) = ".$(ARCHIVE_EXT)" ]; then\
+		$(COMPRESS) $< > /dev/null &&\
+		echo "$< -> $@";\
+	fi
+
+$(LARGE_FILES_GZ_SPLIT): %.$(ARCHIVE_EXT).00.split: %.$(ARCHIVE_EXT)
+	@if [ -n "$$(find "$<" -prune -size +$(FILE_SIZE_LIMIT_MB)M)" ]; then\
+		split $< -b $(FILE_SIZE_LIMIT_MB)M $<. -d &&\
+		rm $< &&\
+		for file in $$(ls $<.*); do mv "$$file" "$$file.split"; done &&\
+		echo -n "$< -> $$(ls $<.*.split)" | tr '\n' ' ' && echo "";\
+	fi
+
+# This target compresses all files larger than $(FILE_SIZE_LIMIT_MB) MB
+.PHONY: compress
+compress: $(LARGE_FILES_GZ) $(LARGE_FILES_GZ_SPLIT)
+	@echo "Files larger than $(FILE_SIZE_LIMIT_MB) MBytes are compressed!"
+
+
+
+#####
+$(ARCHIVE_SOURCES): %: %.$(ARCHIVE_EXT)
+	@$(UNCOMPRESS) $<
+	@echo "$< -> $@"
+
+.SECONDEXPANSION:
+$(SPLIT_FILES_SOURCES): %: $$(sort $$(wildcard %.$(ARCHIVE_EXT).*.split))
+	@cat $? > $@.$(ARCHIVE_EXT)
+	@rm $?
+	@echo "$? -> $@.$(ARCHIVE_EXT)"
+	@$(UNCOMPRESS) $@.$(ARCHIVE_EXT)
+	@echo "$@.$(ARCHIVE_EXT) -> $@"
+
+
+.PHONY: uncompress
+uncompress: $(SPLIT_FILES_SOURCES) $(ARCHIVE_SOURCES)
+	@echo "All files are uncompressed!"
+
+
+# verify that the wrapper was respected
+xor-wrapper: uncompress
+### first erase the user's user_project_wrapper.gds
+	sh $(CARAVEL_ROOT)/utils/erase_box.sh gds/user_project_wrapper.gds 0 0 2920 3520
+### do the same for the empty wrapper
+	sh $(CARAVEL_ROOT)/utils/erase_box.sh $(CARAVEL_ROOT)/gds/user_project_wrapper_empty.gds 0 0 2920 3520
+	mkdir -p signoff/user_project_wrapper_xor
+### XOR the two resulting layouts
+	sh $(CARAVEL_ROOT)/utils/xor.sh \
+		$(CARAVEL_ROOT)/gds/user_project_wrapper_empty_erased.gds gds/user_project_wrapper_erased.gds \
+		user_project_wrapper user_project_wrapper.xor.xml
+	sh $(CARAVEL_ROOT)/utils/xor.sh \
+		$(CARAVEL_ROOT)/gds/user_project_wrapper_empty_erased.gds gds/user_project_wrapper_erased.gds \
+		user_project_wrapper gds/user_project_wrapper.xor.gds > signoff/user_project_wrapper_xor/xor.log 
+	rm $(CARAVEL_ROOT)/gds/user_project_wrapper_empty_erased.gds gds/user_project_wrapper_erased.gds
+	mv gds/user_project_wrapper.xor.gds gds/user_project_wrapper.xor.xml signoff/user_project_wrapper_xor
+	python $(CARAVEL_ROOT)/utils/parse_klayout_xor_log.py \
+		-l signoff/user_project_wrapper_xor/xor.log \
+		-o signoff/user_project_wrapper_xor/total.txt
+### screenshot the result for convenience
+	sh $(CARAVEL_ROOT)/utils/scrotLayout.sh \
+		$(PDK_ROOT)/sky130A/libs.tech/klayout/sky130A.lyt \
+		signoff/user_project_wrapper_xor/user_project_wrapper.xor.gds
+	@cat signoff/user_project_wrapper_xor/total.txt
+
+# verify that the wrapper was respected
+xor-analog-wrapper: uncompress
+### first erase the user's user_project_wrapper.gds
+	sh $(CARAVEL_ROOT)/utils/erase_box.sh gds/user_analog_project_wrapper.gds 0 0 2920 3520
+### do the same for the empty wrapper
+	sh $(CARAVEL_ROOT)/utils/erase_box.sh $(CARAVEL_ROOT)/gds/user_analog_project_wrapper_empty.gds 0 0 2920 3520
+	mkdir -p signoff/user_analog_project_wrapper_xor
+### XOR the two resulting layouts
+	sh $(CARAVEL_ROOT)/utils/xor.sh \
+		$(CARAVEL_ROOT)/gds/user_analog_project_wrapper_empty_erased.gds gds/user_analog_project_wrapper_erased.gds \
+		user_analog_project_wrapper user_analog_project_wrapper.xor.xml
+	sh $(CARAVEL_ROOT)/utils/xor.sh \
+		$(CARAVEL_ROOT)/gds/user_analog_project_wrapper_empty_erased.gds gds/user_analog_project_wrapper_erased.gds \
+		user_analog_project_wrapper gds/user_analog_project_wrapper.xor.gds > signoff/user_analog_project_wrapper_xor/xor.log 
+	rm $(CARAVEL_ROOT)/gds/user_analog_project_wrapper_empty_erased.gds gds/user_analog_project_wrapper_erased.gds
+	mv gds/user_analog_project_wrapper.xor.gds gds/user_analog_project_wrapper.xor.xml signoff/user_analog_project_wrapper_xor
+	python $(CARAVEL_ROOT)/utils/parse_klayout_xor_log.py \
+		-l signoff/user_analog_project_wrapper_xor/xor.log \
+		-o signoff/user_analog_project_wrapper_xor/total.txt
+### screenshot the result for convenience
+	sh $(CARAVEL_ROOT)/utils/scrotLayout.sh \
+		$(PDK_ROOT)/sky130A/libs.tech/klayout/sky130A.lyt \
+		signoff/user_analog_project_wrapper_xor/user_analog_project_wrapper.xor.gds
+	@cat signoff/user_analog_project_wrapper_xor/total.txt
+
+# LVS
+BLOCKS = $(shell cd openlane && find * -maxdepth 0 -type d)
+LVS_BLOCKS = $(foreach block, $(BLOCKS), lvs-$(block))
+$(LVS_BLOCKS): lvs-% : ./mag/%.mag ./verilog/gl/%.v
+	echo "Extracting $*"
+	mkdir -p ./mag/tmp
+	echo "addpath $(CARAVEL_ROOT)/mag/hexdigits;\
+		addpath \$$PDKPATH/libs.ref/sky130_ml_xx_hd/mag;\
+		load $* -dereference;\
+		select top cell;\
+		foreach cell [cellname list children] {\
+			load \$$cell -dereference;\
+			property LEFview TRUE;\
+		};\
+		load $* -dereference;\
+		select top cell;\
+		extract no all;\
+		extract do local;\
+		extract unique;\
+		extract;\
+		ext2spice lvs;\
+		ext2spice $*.ext;\
+		feedback save extract_$*.log;\
+		exit;" > ./mag/extract_$*.tcl
+	cd mag && \
+		export MAGTYPE=maglef; \
+		magic -rcfile ${PDK_ROOT}/sky130A/libs.tech/magic/sky130A.magicrc -noc -dnull extract_$*.tcl < /dev/null
+	mv ./mag/$*.spice ./spi/lvs
+	rm ./mag/*.ext
+	mv -f ./mag/extract_$*.tcl ./mag/tmp
+	mv -f ./mag/extract_$*.log ./mag/tmp
+	####
+	mkdir -p ./spi/lvs/tmp
+	sh $(CARAVEL_ROOT)/spi/lvs/run_lvs.sh ./spi/lvs/$*.spice ./verilog/gl/$*.v $*
+	@echo ""
+	python3 $(CARAVEL_ROOT)/scripts/count_lvs.py -f ./verilog/gl/$*.v_comp.json | tee ./spi/lvs/tmp/$*.lvs.summary.log
+	mv -f ./verilog/gl/*.out ./spi/lvs/tmp 2> /dev/null || true
+	mv -f ./verilog/gl/*.json ./spi/lvs/tmp 2> /dev/null || true
+	mv -f ./verilog/gl/*.log ./spi/lvs/tmp 2> /dev/null || true
+	@echo ""
+	@echo "LVS: ./spi/lvs/$*.spice vs. ./verilog/gl/$*.v"
+	@echo "Comparison result: ./spi/lvs/tmp/$*.v_comp.out"
+	@awk '/^NET mismatches/,0' ./spi/lvs/tmp/$*.v_comp.out
+
+
+LVS_GDS_BLOCKS = $(foreach block, $(BLOCKS), lvs-gds-$(block))
+$(LVS_GDS_BLOCKS): lvs-gds-% : ./gds/%.gds ./verilog/gl/%.v
+	echo "Extracting $*"
+	mkdir -p ./gds/tmp
+	echo "gds read ./$*.gds;\
+		load $* -dereference;\
+		select top cell;\
+		extract no all;\
+		extract do local;\
+		extract unique;\
+		extract;\
+		ext2spice lvs;\
+		ext2spice $*.ext;\
+		feedback save extract_$*.log;\
+		exit;" > ./gds/extract_$*.tcl
+	cd gds && \
+		magic -rcfile ${PDK_ROOT}/sky130A/libs.tech/magic/sky130A.magicrc -noc -dnull extract_$*.tcl < /dev/null
+	mv ./gds/$*.spice ./spi/lvs
+	rm ./gds/*.ext
+	mv -f ./gds/extract_$*.tcl ./gds/tmp
+	mv -f ./gds/extract_$*.log ./gds/tmp
+	####
+	mkdir -p ./spi/lvs/tmp
+	MAGIC_EXT_USE_GDS=1 sh $(CARAVEL_ROOT)/spi/lvs/run_lvs.sh ./spi/lvs/$*.spice ./verilog/gl/$*.v $*
+	@echo ""
+	python3 $(CARAVEL_ROOT)/scripts/count_lvs.py -f ./verilog/gl/$*.v_comp.json | tee ./spi/lvs/tmp/$*.lvs.summary.log
+	mv -f ./verilog/gl/*.out ./spi/lvs/tmp 2> /dev/null || true
+	mv -f ./verilog/gl/*.json ./spi/lvs/tmp 2> /dev/null || true
+	mv -f ./verilog/gl/*.log ./spi/lvs/tmp 2> /dev/null || true
+	@echo ""
+	@echo "LVS: ./spi/lvs/$*.spice vs. ./verilog/gl/$*.v"
+	@echo "Comparison result: ./spi/lvs/tmp/$*.v_comp.out"
+	@awk '/^NET mismatches/,0' ./spi/lvs/tmp/$*.v_comp.out
+
+
+# connect-by-label is enabled here!
+LVS_MAGLEF_BLOCKS = $(foreach block, $(BLOCKS), lvs-maglef-$(block))
+$(LVS_MAGLEF_BLOCKS): lvs-maglef-% : ./mag/%.mag ./verilog/gl/%.v
+	echo "Extracting $*"
+	mkdir -p ./maglef/tmp
+	echo "load $* -dereference;\
+		select top cell;\
+		foreach cell [cellname list children] {\
+			load \$$cell -dereference;\
+			property LEFview TRUE;\
+		};\
+		load $* -dereference;\
+		select top cell;\
+		extract no all;\
+		extract do local;\
+		extract;\
+		ext2spice lvs;\
+		ext2spice $*.ext;\
+		feedback save extract_$*.log;\
+		exit;" > ./mag/extract_$*.tcl
+	cd mag && export MAGTYPE=maglef; magic -noc -dnull extract_$*.tcl < /dev/null
+	mv ./mag/$*.spice ./spi/lvs
+	rm ./mag/*.ext
+	mv -f ./mag/extract_$*.tcl ./maglef/tmp
+	mv -f ./mag/extract_$*.log ./maglef/tmp
+	####
+	mkdir -p ./spi/lvs/tmp
+	sh $(CARAVEL_ROOT)/spi/lvs/run_lvs.sh ./spi/lvs/$*.spice ./verilog/gl/$*.v $*
+	@echo ""
+	python3 $(CARAVEL_ROOT)/scripts/count_lvs.py -f ./verilog/gl/$*.v_comp.json | tee ./spi/lvs/tmp/$*.maglef.lvs.summary.log
+	mv -f ./verilog/gl/*{.out,.json,.log} ./spi/lvs/tmp 2> /dev/null || true
+	@echo ""
+	@echo "LVS: ./spi/lvs/$*.spice vs. ./verilog/gl/$*.v"
+	@echo "Comparison result: ./spi/lvs/tmp/$*.v_comp.out"
+	@awk '/^NET mismatches/,0' ./spi/lvs/tmp/$*.v_comp.out
+
+# DRC
+BLOCKS = $(shell cd openlane && find * -maxdepth 0 -type d)
+DRC_BLOCKS = $(foreach block, $(BLOCKS), drc-$(block))
+$(DRC_BLOCKS): drc-% : ./gds/%.gds
+	echo "Running DRC on $*"
+	mkdir -p ./gds/tmp
+	cd gds && export DESIGN_IN_DRC=$* && export MAGTYPE=mag; magic -rcfile ${PDK_ROOT}/sky130A/libs.tech/magic/sky130A.magicrc -noc -dnull $(CARAVEL_ROOT)/gds/drc_on_gds.tcl < /dev/null
+	@echo "DRC result: ./gds/tmp/$*.drc"
+
+# Antenna
+BLOCKS = $(shell cd openlane && find * -maxdepth 0 -type d)
+ANTENNA_BLOCKS = $(foreach block, $(BLOCKS), antenna-$(block))
+$(ANTENNA_BLOCKS): antenna-% : ./gds/%.gds
+	echo "Running Antenna Checks on $*"
+	mkdir -p ./gds/tmp
+	cd gds && export DESIGN_IN_ANTENNA=$* && export MAGTYPE=mag; magic -rcfile ${PDK_ROOT}/sky130A/libs.tech/magic/sky130A.magicrc -noc -dnull $(CARAVEL_ROOT)/gds/antenna_on_gds.tcl < /dev/null 2>&1 | tee ./tmp/$*.antenna
+	mv -f ./gds/*.ext ./gds/tmp/
+	@echo "Antenna result: ./gds/tmp/$*.antenna"
+
+.PHONY: help
+help:
+	@$(MAKE) -pRrq -f $(lastword $(MAKEFILE_LIST)) : 2>/dev/null | awk -v RS= -F: '/^# File/,/^# Finished Make data base/ {if ($$1 !~ "^[#.]") {print $$1}}' | sort | egrep -v -e '^[^[:alnum:]]' -e '^$@$$'
+
+.PHONY: generate_fill
+generate_fill: check-env check-uid uncompress
+ifeq ($(FOREGROUND),1)
+	@echo "Running generate_fill in the foreground..."
+	$(MAKE) __generate_fill
+	@echo "Generate fill completed." 2>&1 | tee -a ./signoff/build/generate_fill.out
+else
+	@echo "Running generate_fill in the background..."
+	@nohup $(MAKE) __generate_fill >/dev/null 2>&1 &
+	tail -f signoff/build/generate_fill.out
+	@echo "Generate fill completed." | tee -a signoff/build/generate_fill.out
+endif
+
+__generate_fill:
+	@mkdir -p ./signoff/build
+	@cp -r $(CARAVEL_ROOT)/mag/.magicrc $(shell pwd)/mag
+	python3 $(CARAVEL_ROOT)/scripts/generate_fill.py $(USER_ID) $(shell pwd) -dist 2>&1 | tee ./signoff/build/generate_fill.out
+
+
+.PHONY: final
+final: check-env check-uid uncompress
+ifeq ($(FOREGROUND),1)
+	$(MAKE) __final
+	@echo "Final build completed." 2>&1 | tee -a ./signoff/build/final_build.out
+else
+	$(MAKE) __final >/dev/null 2>&1 &
+	tail -f signoff/build/final_build.out
+	@echo "Final build completed." 2>&1 | tee -a ./signoff/build/final_build.out
+endif
+
+__final:
+	mkdir -p ./mag/tmp 
+	cp -r ./mag/*.mag ./mag/tmp
+	cp -r $(CARAVEL_ROOT)/mag/* mag/tmp/
+	cp -r $(CARAVEL_ROOT)/mag/.magicrc mag/tmp/
+	sed -i 's@../gds@../../$(CARAVEL_ROOT)/gds@g' ./mag/tmp/*.mag
+	sed -i 's@../maglef@../../$(CARAVEL_ROOT)/maglef@g' ./mag/tmp/caravel.mag
+	sed -i 's@../subcells@../../$(CARAVEL_ROOT)/subcells@g' ./mag/tmp/.magicrc
+	python3 $(CARAVEL_ROOT)/scripts/compositor.py $(USER_ID) $(shell pwd) $(shell pwd)/mag/tmp $(shell pwd)/gds
+	@rm -rf ./mag/tmp
+
+.PHONY: set_user_id
+set_user_id: check-env check-uid uncompress
+ifeq ($(FOREGROUND),1)
+	$(MAKE) __set_user_id 
+	@echo "Set user ID completed." 2>&1 | tee -a ./signoff/build/set_user_id.out
+else
+	$(MAKE) __set_user_id >/dev/null 2>&1 &
+	tail -f signoff/build/set_user_id.out
+	@echo "Set user ID completed." 2>&1 | tee -a ./signoff/build/set_user_id.out
+endif
+
+__set_user_id: 
+	mkdir -p ./signoff/build
+	# Update info.yaml
+	sed -r "s/^(\s*project_id\s*:\s*).*/\1${USER_ID}/" -i info.yaml
+	python3 $(CARAVEL_ROOT)/scripts/set_user_id.py $(USER_ID) $(CARAVEL_ROOT) 2>&1 | tee ./signoff/build/set_user_id.out
+
+.PHONY: update_caravel
+update_caravel:
+	cd caravel/ && \
+		git checkout master && \
+		git pull
+
+###########################################################################
+.PHONY: pdk
+pdk: skywater-pdk skywater-library skywater-timing open_pdks build-pdk gen-sources
+
+$(PDK_ROOT)/skywater-pdk:
+	git clone https://github.com/google/skywater-pdk.git $(PDK_ROOT)/skywater-pdk
+
+.PHONY: skywater-pdk
+skywater-pdk: check-env $(PDK_ROOT)/skywater-pdk
+	cd $(PDK_ROOT)/skywater-pdk && \
+		git checkout main && git pull && \
+		git checkout -qf $(SKYWATER_COMMIT)
+
+.PHONY: skywater-library
+skywater-library: check-env $(PDK_ROOT)/skywater-pdk
+	cd $(PDK_ROOT)/skywater-pdk && \
+		git submodule update --init libraries/$(STD_CELL_LIBRARY)/latest && \
+		git submodule update --init libraries/$(IO_LIBRARY)/latest && \
+		git submodule update --init libraries/$(SPECIAL_VOLTAGE_LIBRARY)/latest && \
+		git submodule update --init libraries/$(PRIMITIVES_LIBRARY)/latest
+
+gen-sources: $(PDK_ROOT)/sky130A
+	touch $(PDK_ROOT)/sky130A/SOURCES
+	echo -ne "skywater-pdk " >> $(PDK_ROOT)/sky130A/SOURCES
+	cd $(PDK_ROOT)/skywater-pdk && git rev-parse HEAD >> $(PDK_ROOT)/sky130A/SOURCES
+	echo -ne "open_pdks " >> $(PDK_ROOT)/sky130A/SOURCES
+	cd $(PDK_ROOT)/open_pdks && git rev-parse HEAD >> $(PDK_ROOT)/sky130A/SOURCES
+
+skywater-timing: check-env $(PDK_ROOT)/skywater-pdk
+	cd $(PDK_ROOT)/skywater-pdk && \
+		$(MAKE) timing
+### OPEN_PDKS
+$(PDK_ROOT)/open_pdks:
+	git clone https://github.com/RTimothyEdwards/open_pdks.git $(PDK_ROOT)/open_pdks
+
+.PHONY: open_pdks
+open_pdks: check-env $(PDK_ROOT)/open_pdks
+	cd $(PDK_ROOT)/open_pdks && \
+		git checkout master && git pull && \
+		git checkout -qf $(OPEN_PDKS_COMMIT)
+
+.PHONY: build-pdk
+build-pdk: check-env $(PDK_ROOT)/open_pdks $(PDK_ROOT)/skywater-pdk
+	[ -d $(PDK_ROOT)/sky130A ] && \
+		(echo "Warning: A sky130A build already exists under $(PDK_ROOT). It will be deleted first!" && \
+		sleep 5 && \
+		rm -rf $(PDK_ROOT)/sky130A) || \
+		true
+	cd $(PDK_ROOT)/open_pdks && \
+		./configure --enable-sky130-pdk=$(PDK_ROOT)/skywater-pdk/libraries --with-sky130-local-path=$(PDK_ROOT) --disable-sram-sky130 && \
+		cd sky130 && \
+		$(MAKE) veryclean && \
+		$(MAKE) && \
+		$(MAKE) install-local && \
+		$(MAKE) clean
+
+.RECIPE: manifest
+manifest: mag/ maglef/ verilog/rtl/ scripts/ Makefile
+	touch manifest && \
+	find verilog/rtl/* -type f ! -name "caravel_netlists.v" ! -name "user_*.v" ! -name "README" ! -name "defines.v" -exec shasum {} \; > manifest && \
+	shasum scripts/set_user_id.py scripts/generate_fill.py scripts/compositor.py >> manifest
+# shasum lef/user_project_wrapper_empty.lef >> manifest
+# find maglef/*.mag -type f ! -name "user_project_wrapper.mag" -exec shasum {} \; >> manifest && \
+# shasum mag/caravel.mag mag/.magicrc >> manifest
+
+check-env:
+ifndef PDK_ROOT
+	$(error PDK_ROOT is undefined, please export it before running make)
+endif
+
+check-uid:
+ifndef USER_ID
+	$(error USER_ID is undefined, please export it before running make set_user_id)
+else 
+	@echo USER_ID is set to $(USER_ID)
+endif
+
+# Make README.rst
+README.rst: README.src.rst docs/source/getting-started.rst docs/source/tool-versioning.rst openlane/README.src.rst docs/source/caravel-with-openlane.rst Makefile
+	pip -q install rst_include && \
+	rm -f README.rst && \
+		rst_include include README.src.rst - | \
+			sed \
+				-e's@\.\/\_static@\/docs\/source\/\_static@g' \
+				-e's@:doc:`tool-versioning`@`tool-versioning.rst <./docs/source/tool-versioning.rst>`__@g' \
+				-e's@.. note::@**NOTE:**@g' \
+				-e's@.. warning::@**WARNING:**@g' \
+				> README.rst && \
+		rst_include include openlane/README.src.rst - | \
+			sed \
+				-e's@https://github.com/efabless/caravel/blob/master/verilog@../verilog@g' \
+				-e's@:ref:`getting-started`@`README.rst <../README.rst>`__@g' \
+				-e's@https://github.com/efabless/caravel/blob/master/openlane/@./@g' \
+				-e's@.. note::@**NOTE:**@g' \
+				-e's@.. warning::@**WARNING:**@g' \
+				> openlane/README.rst
diff --git a/caravel/gds/antenna_on_gds.tcl b/caravel/gds/antenna_on_gds.tcl
new file mode 100644
index 0000000..5f379c6
--- /dev/null
+++ b/caravel/gds/antenna_on_gds.tcl
@@ -0,0 +1,28 @@
+# SPDX-FileCopyrightText: 2020 Efabless Corporation
+#
+# Licensed under the Apache License, Version 2.0 (the "License");
+# you may not use this file except in compliance with the License.
+# You may obtain a copy of the License at
+#
+#      http://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing, software
+# distributed under the License is distributed on an "AS IS" BASIS,
+# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+# See the License for the specific language governing permissions and
+# limitations under the License.
+# SPDX-License-Identifier: Apache-2.0
+
+gds read $::env(DESIGN_IN_ANTENNA).gds
+select top cell
+extract do local
+extract no capacitance
+extract no coupling
+extract no resistance
+extract no adjust
+extract unique
+# extract warn all
+extract
+feedback save ./tmp/$::env(DESIGN_IN_ANTENNA)_ext2spice.antenna.feedback.txt
+antennacheck debug
+antennacheck
diff --git a/caravel/gds/drc_on_gds.tcl b/caravel/gds/drc_on_gds.tcl
new file mode 100644
index 0000000..8bb3035
--- /dev/null
+++ b/caravel/gds/drc_on_gds.tcl
@@ -0,0 +1,61 @@
+# SPDX-FileCopyrightText: 2020 Efabless Corporation
+#
+# Licensed under the Apache License, Version 2.0 (the "License");
+# you may not use this file except in compliance with the License.
+# You may obtain a copy of the License at
+#
+#      http://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing, software
+# distributed under the License is distributed on an "AS IS" BASIS,
+# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+# See the License for the specific language governing permissions and
+# limitations under the License.
+# SPDX-License-Identifier: Apache-2.0
+
+gds read $::env(DESIGN_IN_DRC).gds
+set fout [open ./tmp/$::env(DESIGN_IN_DRC).drc w]
+set oscale [cif scale out]
+set cell_name $::env(DESIGN_IN_DRC)
+magic::suspendall
+puts stdout "\[INFO\]: Loading $::env(DESIGN_IN_DRC)\n"
+flush stdout
+load $::env(DESIGN_IN_DRC)
+select top cell
+drc euclidean on
+drc style drc(full)
+drc check
+set drcresult [drc listall why]
+set count 0
+puts $fout "$::env(DESIGN_IN_DRC)"
+puts $fout "----------------------------------------"
+foreach {errtype coordlist} $drcresult {
+    puts $fout $errtype
+    puts $fout "----------------------------------------"
+    foreach coord $coordlist {
+        set bllx [expr {$oscale * [lindex $coord 0]}]
+        set blly [expr {$oscale * [lindex $coord 1]}]
+        set burx [expr {$oscale * [lindex $coord 2]}]
+        set bury [expr {$oscale * [lindex $coord 3]}]
+        set coords [format " %.3f %.3f %.3f %.3f" $bllx $blly $burx $bury]
+        puts $fout "$coords"
+        set count [expr {$count + 1} ]
+    }
+    puts $fout "----------------------------------------"
+}
+
+puts $fout "\[INFO\]: COUNT: $count"
+puts $fout "\[INFO\]: Should be divided by 3 or 4"
+
+puts $fout ""
+close $fout
+
+puts stdout "\[INFO\]: COUNT: $count"
+puts stdout "\[INFO\]: Should be divided by 3 or 4"
+puts stdout "\[INFO\]: DRC Checking DONE (./tmp/$::env(DESIGN_IN_DRC).drc)"
+flush stdout
+
+puts stdout "\[INFO\]: Saving mag view with DRC errors(./tmp/$::env(DESIGN_IN_DRC).drc.mag)"
+# WARNING: changes the name of the cell; keep as last step
+save ./tmp/$::env(DESIGN_IN_DRC).drc.drc.mag
+puts stdout "\[INFO\]: Saved"
diff --git a/caravel/gds/gds2mag-all.sh b/caravel/gds/gds2mag-all.sh
new file mode 100644
index 0000000..b9ca6f2
--- /dev/null
+++ b/caravel/gds/gds2mag-all.sh
@@ -0,0 +1,34 @@
+#!/bin/sh
+# SPDX-FileCopyrightText: 2020 Efabless Corporation
+#
+# Licensed under the Apache License, Version 2.0 (the "License");
+# you may not use this file except in compliance with the License.
+# You may obtain a copy of the License at
+#
+#      http://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing, software
+# distributed under the License is distributed on an "AS IS" BASIS,
+# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+# See the License for the specific language governing permissions and
+# limitations under the License.
+# SPDX-License-Identifier: Apache-2.0
+
+
+
+gunzip *.gz
+mv sram_1rw1r_32_256_8_sky130_lp1.gds sram_1rw1r_32_256_8_sky130.gds
+
+o-gds2mag-mag.sh simple_por.gds 
+o-gds2mag-mag.sh gpio_control_block.gds
+o-gds2mag-mag.sh digital_pll.gds
+o-gds2mag-mag.sh storage.gds
+o-gds2mag-mag.sh mgmt_core.gds
+o-gds2mag-mag.sh chip_io.gds
+o-gds2mag-mag.sh sram_1rw1r_32_256_8_sky130.gds
+
+mv -f *.mag ../mag
+
+gzip -9 storage.gds mgmt_core.gds chip_io.gds
+
+
diff --git a/caravel/gds/user_project_wrapper.gds.gz b/caravel/gds/user_project_wrapper.gds.gz
new file mode 100644
index 0000000..a060021
--- /dev/null
+++ b/caravel/gds/user_project_wrapper.gds.gz
Binary files differ
diff --git a/caravel/gds/user_project_wrapper_empty.gds.gz b/caravel/gds/user_project_wrapper_empty.gds.gz
new file mode 100644
index 0000000..53e60a7
--- /dev/null
+++ b/caravel/gds/user_project_wrapper_empty.gds.gz
Binary files differ
diff --git a/caravel/info.yaml b/caravel/info.yaml
new file mode 100644
index 0000000..16388ef
--- /dev/null
+++ b/caravel/info.yaml
@@ -0,0 +1,19 @@
+--- 
+project: 
+  description: "A template SoC for Google sponsored Open MPW shuttles for SKY130."
+  foundry: "SkyWater"
+  git_url: "https://github.com/efabless/caravel.git"
+  organization: "Efabless"
+  organization_url: "http://efabless.com"
+  owner: "Tim Edwards"
+  process: "SKY130"
+  project_name: "Caravel"
+  project_id: "00000000"
+  tags: 
+    - "Open MPW"
+    - "Test Harness"
+  category: "Test Harness"
+  top_level_netlist: "verilog/gl/caravel.v"
+  user_level_netlist: "verilog/gl/user_project_wrapper.v"
+  version: "1.00"
+  cover_image: "docs/source/_static/caravel_harness.png"
diff --git a/caravel/manifest b/caravel/manifest
new file mode 100644
index 0000000..798bc8b
--- /dev/null
+++ b/caravel/manifest
@@ -0,0 +1,47 @@
+d328f88dd48e015bbaa95e0d7c88954343cc5632  verilog/rtl/DFFRAM.v
+dab57f3c5464ce3354219840dae589a3fcd27135  verilog/rtl/DFFRAMBB.v
+535d0592c0b1349489b6b86fd5449f9d1d81482e  verilog/rtl/__uprj_analog_netlists.v
+87735eb5981740ca4d4b48e6b0321c8bb0023800  verilog/rtl/__uprj_netlists.v
+ef9cf827273c2a245f807725f33bb3bc6e51ba54  verilog/rtl/__user_analog_project_wrapper.v
+c3616f10b8d437432a30dc0dbf2235d50c4f5847  verilog/rtl/__user_project_wrapper.v
+6229bc5cbbe404575340153b4274033ca8d66c38  verilog/rtl/caravan.v
+31775f9c43c80b137a1cbbc9dd78e4e96708a8e9  verilog/rtl/caravan_netlists.v
+6ff514c11754375cd9c86229d4466c071617e8c2  verilog/rtl/caravel.v
+b2feeb2a098894d5d731a5b011858a471e855d73  verilog/rtl/caravel_clocking.v
+7c4b2a8c1a70bbf13291f25973a4f776c804909e  verilog/rtl/chip_io.v
+a6f9dbe63659a716d85f646b14421b9ad0425186  verilog/rtl/chip_io_alt.v
+d772308bd2a72121d7ed9dcdd40c8e6cbbe4b43c  verilog/rtl/clock_div.v
+f937b52e53d45bdbe41bcbd07c65b41104c21756  verilog/rtl/convert_gpio_sigs.v
+21204dc96bdb3c1295dd06375293ee3d811d2f7e  verilog/rtl/counter_timer_high.v
+6b9b2ab85a85f73d6ce686c67fc85e59d9623ee6  verilog/rtl/counter_timer_low.v
+fff2d08e49701312c2ebd6714b7425baf83f3d35  verilog/rtl/digital_pll.v
+ce49f9af199b5f16d2c39c417d58e5890bc7bab2  verilog/rtl/digital_pll_controller.v
+89dee515f5819e4f5d572f9542ca19798f4b6c4e  verilog/rtl/gpio_control_block.v
+57554b3586f306944b31718a8c52526fa9a8a574  verilog/rtl/gpio_wb.v
+baf3aba29655ca7021398ddc3f68be81eff0fa0c  verilog/rtl/housekeeping_spi.v
+6c11ee92e0b2995982041d8a599b5d46b7dde838  verilog/rtl/la_wb.v
+ff3e65a783f3807340e25efac9207787d39fb6cd  verilog/rtl/mem_wb.v
+0894819fdfdcc1cb7a0fcacca3ac133f9884cc5a  verilog/rtl/mgmt_core.v
+65934e08f3ad2d5fbacd8fc68eae0bb485c25309  verilog/rtl/mgmt_protect.v
+3b1ff20593bc386d13f5e2cf1571f08121889957  verilog/rtl/mgmt_protect_hv.v
+85bc308843b6aad96ac9e75f49c942db8e1c0afe  verilog/rtl/mgmt_soc.v
+9816acedf3dc3edd193861cc217ec46180ac1cdd  verilog/rtl/mprj2_logic_high.v
+b4395fbd17108e58e33a620159464ae944a15878  verilog/rtl/mprj_ctrl.v
+a61f5566f5d369d879c47d6b65f99cf297debe8f  verilog/rtl/mprj_io.v
+b928ab6205a267f6ac83c603965c6f34a486724e  verilog/rtl/mprj_logic_high.v
+eac1e6d413cdfbc2f802e229ae5058828e01be1e  verilog/rtl/pads.v
+b5aff2fda5078cfda377b98337fcc91040815fc2  verilog/rtl/picorv32.v
+669d16642d5dd5f6824812754db20db98c9fe17b  verilog/rtl/ring_osc2x13.v
+6864cc10dacfd3edb4c66825b7a301ab097cea0d  verilog/rtl/simple_por.v
+917aa6e1bb869f973c79fb2c7894eab882ead74c  verilog/rtl/simple_spi_master.v
+d43221ffa0f2d760991d8b911b4a5292911203f5  verilog/rtl/simpleuart.v
+46bca62460c4dbfac30233318b24c3d526a40058  verilog/rtl/sky130_fd_sc_hvl__lsbufhv2lv_1_wrapped.v
+eb0c856ab69e8c364c04bdc149db9d82ae67b39d  verilog/rtl/spimemio.v
+3b4c3de623f8af0f0780f1e5b0f2217ef6406a2f  verilog/rtl/sram_1rw1r_32_256_8_sky130.v
+da42d868bfe847b83ed0a3e6e8307216a6f3fa21  verilog/rtl/storage.v
+7e8d789570ed224df49cf61f69593cc738790a5d  verilog/rtl/storage_bridge_wb.v
+5e314e94a13d7291117123395ae088e1d17cf487  verilog/rtl/sysctrl.v
+e6246df6bbf0860a331b3547d64f7d235b0eca9a  verilog/rtl/wb_intercon.v
+9d06bd68e8ec6918cd3ef5467cb8cee44e7e3a26  scripts/set_user_id.py
+be50a23e39bf13eed5090ac819b785afdba587b0  scripts/generate_fill.py
+e3793327393803e44a90a702c5413facbb4b46e8  scripts/compositor.py
diff --git a/caravel/openlane/Makefile b/caravel/openlane/Makefile
new file mode 100644
index 0000000..6386c39
--- /dev/null
+++ b/caravel/openlane/Makefile
@@ -0,0 +1,85 @@
+# SPDX-FileCopyrightText: 2020 Efabless Corporation
+#
+# Licensed under the Apache License, Version 2.0 (the "License");
+# you may not use this file except in compliance with the License.
+# You may obtain a copy of the License at
+#
+#      http://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing, software
+# distributed under the License is distributed on an "AS IS" BASIS,
+# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+# See the License for the specific language governing permissions and
+# limitations under the License.
+#
+# SPDX-License-Identifier: Apache-2.0
+
+BLOCKS = $(shell find * -maxdepth 0 -type d)
+CONFIG = $(foreach block,$(BLOCKS), ./$(block)/config.tcl)
+CLEAN = $(foreach block,$(BLOCKS), clean-$(block))
+
+OPENLANE_TAG ?= v0.14
+OPENLANE_IMAGE_NAME ?= efabless/openlane:$(OPENLANE_TAG)
+OPENLANE_BASIC_COMMAND = "cd /project/openlane && flow.tcl -design ./$* -save_path .. -save -tag $* -overwrite"
+OPENLANE_INTERACTIVE_COMMAND = "cd /project/openlane && flow.tcl -it -file ./$*/interactive.tcl"
+
+all: $(BLOCKS)
+
+$(CONFIG) :
+	@echo "Missing $@. Please create a configuration for that design"
+	@exit 1
+
+$(BLOCKS) : % : ./%/config.tcl FORCE
+ifeq ($(OPENLANE_ROOT),)
+	@echo "Please export OPENLANE_ROOT"
+	@exit 1
+endif
+ifeq ($(PDK_ROOT),)
+	@echo "Please export PDK_ROOT"
+	@exit 1
+endif
+	@echo "###############################################"
+	@sleep 1
+
+	@if [ -f ./$*/interactive.tcl ]; then\
+		docker run -it -v $(OPENLANE_ROOT):/openLANE_flow \
+		-v $(PDK_ROOT):$(PDK_ROOT) \
+		-v $(PWD)/..:/project \
+		-e PDK_ROOT=$(PDK_ROOT) \
+		-u $(shell id -u $(USER)):$(shell id -g $(USER)) \
+		$(OPENLANE_IMAGE_NAME) sh -c $(OPENLANE_INTERACTIVE_COMMAND);\
+	else\
+		docker run -it -v $(OPENLANE_ROOT):/openLANE_flow \
+		-v $(PDK_ROOT):$(PDK_ROOT) \
+		-v $(PWD)/..:/project \
+		-e PDK_ROOT=$(PDK_ROOT) \
+		-u $(shell id -u $(USER)):$(shell id -g $(USER)) \
+		$(OPENLANE_IMAGE_NAME) sh -c $(OPENLANE_BASIC_COMMAND);\
+	fi
+	mkdir -p ../signoff/$*/
+	cp $*/runs/$*/OPENLANE_VERSION ../signoff/$*/
+	cp $*/runs/$*/PDK_SOURCES ../signoff/$*/
+	cp $*/runs/$*/reports/final_summary_report.csv ../signoff/$*/
+
+.PHONY: openlane
+openlane:
+ifeq ($(OPENLANE_ROOT),)
+	@echo "Please export OPENLANE_ROOT"
+	@exit 1
+endif
+	git clone https://github.com/efabless/openlane.git --branch=$(OPENLANE_TAG) --depth=1 $(OPENLANE_ROOT) && \
+		cd $(OPENLANE_ROOT) && \
+		make openlane
+
+FORCE:
+
+clean:
+	@echo "Use clean_all to clean everything :)"
+
+clean_all: $(CLEAN)
+
+$(CLEAN): clean-% :
+	rm -rf runs/$*
+	rm -rf ../gds/$**
+	rm -rf ../mag/$**
+	rm -rf ../lef/$**
diff --git a/caravel/openlane/user_project_wrapper_empty/config.tcl b/caravel/openlane/user_project_wrapper_empty/config.tcl
new file mode 100644
index 0000000..8cea6cd
--- /dev/null
+++ b/caravel/openlane/user_project_wrapper_empty/config.tcl
@@ -0,0 +1,43 @@
+# SPDX-FileCopyrightText: 2020 Efabless Corporation
+#
+# Licensed under the Apache License, Version 2.0 (the "License");
+# you may not use this file except in compliance with the License.
+# You may obtain a copy of the License at
+#
+#      http://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing, software
+# distributed under the License is distributed on an "AS IS" BASIS,
+# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+# See the License for the specific language governing permissions and
+# limitations under the License.
+# SPDX-License-Identifier: Apache-2.0
+
+set script_dir [file dirname [file normalize [info script]]]
+source $script_dir/fixed_wrapper_cfgs.tcl
+
+set ::env(DESIGN_NAME) user_project_wrapper
+
+set ::env(FP_PDN_CHECK_NODES) 0
+
+# set ::env(PDN_CFG) $script_dir/pdn.tcl
+
+set ::env(GLB_RT_OBS) "met1 0 0 $::env(DIE_AREA),\
+					   met2 0 0 $::env(DIE_AREA),\
+					   met3 0 0 $::env(DIE_AREA),\
+					   met4 0 0 $::env(DIE_AREA),\
+					   met5 0 0 $::env(DIE_AREA)"
+
+set ::env(CLOCK_PORT) "user_clock2"
+set ::env(CLOCK_NET) "mprj.clk"
+
+set ::env(CLOCK_PERIOD) "10"
+
+set ::env(PL_OPENPHYSYN_OPTIMIZATIONS) 0
+set ::env(DIODE_INSERTION_STRATEGY) 0
+
+set ::env(MAGIC_WRITE_FULL_LEF) 1
+
+set ::env(VERILOG_FILES) "\
+	$script_dir/../../verilog/rtl/defines.v \
+	$script_dir/../../verilog/rtl/__user_project_wrapper.v"
diff --git a/caravel/openlane/user_project_wrapper_empty/fixed_wrapper_cfgs.tcl b/caravel/openlane/user_project_wrapper_empty/fixed_wrapper_cfgs.tcl
new file mode 100644
index 0000000..6893d94
--- /dev/null
+++ b/caravel/openlane/user_project_wrapper_empty/fixed_wrapper_cfgs.tcl
@@ -0,0 +1,60 @@
+# SPDX-FileCopyrightText: 2020 Efabless Corporation
+#
+# Licensed under the Apache License, Version 2.0 (the "License");
+# you may not use this file except in compliance with the License.
+# You may obtain a copy of the License at
+#
+#      http://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing, software
+# distributed under the License is distributed on an "AS IS" BASIS,
+# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+# See the License for the specific language governing permissions and
+# limitations under the License.
+# SPDX-License-Identifier: Apache-2.0
+
+# DON'T TOUCH THE FOLLOWING SECTIONS
+
+# This makes sure that the core rings are outside the boundaries
+# of your block.
+set ::env(MAGIC_ZEROIZE_ORIGIN) 0
+
+# Area Configurations. DON'T TOUCH.
+set ::env(FP_SIZING) absolute
+set ::env(DIE_AREA) "0 0 2920 3520"
+
+set ::env(RUN_CVC) 0
+
+# Pin Configurations. DON'T TOUCH
+set ::env(FP_PIN_ORDER_CFG) $script_dir/pin_order.cfg
+
+set ::unit 2.4
+set ::env(FP_IO_VEXTEND) [expr 2*$::unit]
+set ::env(FP_IO_HEXTEND) [expr 2*$::unit]
+set ::env(FP_IO_VLENGTH) $::unit
+set ::env(FP_IO_HLENGTH) $::unit
+
+set ::env(FP_IO_VTHICKNESS_MULT) 4
+set ::env(FP_IO_HTHICKNESS_MULT) 4
+
+# Power & Pin Configurations. DON'T TOUCH.
+set ::env(FP_PDN_CORE_RING) 1
+set ::env(FP_PDN_CORE_RING_VWIDTH) 3
+set ::env(FP_PDN_CORE_RING_HWIDTH) $::env(FP_PDN_CORE_RING_VWIDTH)
+set ::env(FP_PDN_CORE_RING_VOFFSET) 14
+set ::env(FP_PDN_CORE_RING_HOFFSET) $::env(FP_PDN_CORE_RING_VOFFSET)
+set ::env(FP_PDN_CORE_RING_VSPACING) 1.7
+set ::env(FP_PDN_CORE_RING_HSPACING) $::env(FP_PDN_CORE_RING_VSPACING)
+
+set ::env(FP_PDN_VWIDTH) 3
+set ::env(FP_PDN_HWIDTH) 3
+set ::env(FP_PDN_VOFFSET) 5
+set ::env(FP_PDN_HOFFSET) $::env(FP_PDN_VOFFSET)
+set ::env(FP_PDN_VPITCH) 180
+set ::env(FP_PDN_HPITCH) $::env(FP_PDN_VPITCH)
+set ::env(FP_PDN_VSPACING) [expr 5*$::env(FP_PDN_CORE_RING_VWIDTH)]
+set ::env(FP_PDN_HSPACING) [expr 5*$::env(FP_PDN_CORE_RING_HWIDTH)]
+
+set ::env(VDD_NETS) [list {vccd1} {vccd2} {vdda1} {vdda2}]
+set ::env(GND_NETS) [list {vssd1} {vssd2} {vssa1} {vssa2}]
+set ::env(SYNTH_USE_PG_PINS_DEFINES) "USE_POWER_PINS"
diff --git a/caravel/openlane/user_project_wrapper_empty/interactive.tcl b/caravel/openlane/user_project_wrapper_empty/interactive.tcl
new file mode 100644
index 0000000..059d439
--- /dev/null
+++ b/caravel/openlane/user_project_wrapper_empty/interactive.tcl
@@ -0,0 +1,71 @@
+# SPDX-FileCopyrightText: 2020 Efabless Corporation
+#
+# Licensed under the Apache License, Version 2.0 (the "License");
+# you may not use this file except in compliance with the License.
+# You may obtain a copy of the License at
+#
+#      http://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing, software
+# distributed under the License is distributed on an "AS IS" BASIS,
+# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+# See the License for the specific language governing permissions and
+# limitations under the License.
+# SPDX-License-Identifier: Apache-2.0
+
+package require openlane
+set script_dir [file dirname [file normalize [info script]]]
+
+prep -design $script_dir -tag user_project_wrapper_empty -overwrite
+set save_path $script_dir/../..
+
+verilog_elaborate
+
+init_floorplan
+
+# making it "empty"
+remove_nets -input $::env(CURRENT_DEF)
+remove_components -input $::env(CURRENT_DEF)
+
+place_io_ol
+
+# add_macro_obs \
+# 	-defFile $::env(CURRENT_DEF) \
+# 	-lefFile $::env(MERGED_LEF_UNPADDED) \
+# 	-obstruction core_obs \
+# 	-placementX $::env(FP_IO_HLENGTH) \
+# 	-placementY $::env(FP_IO_VLENGTH) \
+# 	-sizeWidth  [expr [lindex $::env(DIE_AREA) 2]-$::env(FP_IO_HLENGTH)*2] \
+# 	-sizeHeight [expr [lindex $::env(DIE_AREA) 3]-$::env(FP_IO_VLENGTH)*2] \
+# 	-fixed 1 \
+# 	-layerNames "met1 met2 met3 met4 met5"
+
+# exec -ignorestderr openroad -exit $script_dir/gen_pdn.tcl
+
+apply_route_obs
+
+run_power_grid_generation
+
+# set_def $::env(pdn_tmp_file_tag).def
+
+run_magic
+
+save_views       -lef_path $::env(magic_result_file_tag).lef \
+                 -def_path $::env(CURRENT_DEF) \
+                 -gds_path $::env(magic_result_file_tag).gds \
+                 -mag_path $::env(magic_result_file_tag).mag \
+                 -save_path $save_path \
+                 -tag $::env(RUN_TAG)
+
+# produce "obstructed" LEF to be used for routing
+set gap 0.4
+set llx [expr [lindex $::env(DIE_AREA) 0]-$gap]
+set lly [expr [lindex $::env(DIE_AREA) 1]-$gap]
+set urx [expr [lindex $::env(DIE_AREA) 2]+$gap]
+set ury [expr [lindex $::env(DIE_AREA) 3]+$gap]
+exec python3 $::env(OPENLANE_ROOT)/scripts/rectify.py $llx $lly $urx $ury \
+	< $::env(magic_result_file_tag).lef \
+	| python3 $::env(OPENLANE_ROOT)/scripts/obs.py {*}$::env(DIE_AREA) li1 met1 met2 met3 \
+	| python3 $::env(OPENLANE_ROOT)/scripts/obs.py -42.88 -37.53 2962.50 3557.21 met4 met5 \
+	> $::env(magic_result_file_tag).obstructed.lef
+file copy -force $::env(magic_result_file_tag).obstructed.lef $save_path/lef
diff --git a/caravel/openlane/user_project_wrapper_empty/pdn.tcl b/caravel/openlane/user_project_wrapper_empty/pdn.tcl
new file mode 100644
index 0000000..99d74b1
--- /dev/null
+++ b/caravel/openlane/user_project_wrapper_empty/pdn.tcl
@@ -0,0 +1,51 @@
+# SPDX-FileCopyrightText: 2020 Efabless Corporation
+#
+# Licensed under the Apache License, Version 2.0 (the "License");
+# you may not use this file except in compliance with the License.
+# You may obtain a copy of the License at
+#
+#      http://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing, software
+# distributed under the License is distributed on an "AS IS" BASIS,
+# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+# See the License for the specific language governing permissions and
+# limitations under the License.
+# SPDX-License-Identifier: Apache-2.0
+
+# Power nets
+if { ! [info exists ::env(VDD_NET)] } {
+	set ::env(VDD_NET) $::env(VDD_PIN)
+}
+
+if { ! [info exists ::env(GND_NET)] } {
+	set ::env(GND_NET) $::env(GND_PIN)
+}
+
+set ::power_nets $::env(VDD_NET)
+set ::ground_nets $::env(GND_NET)
+
+
+pdngen::specify_grid stdcell {
+    name grid
+	core_ring {
+		$::env(FP_PDN_LOWER_LAYER) {width $::env(FP_PDN_CORE_RING_VWIDTH) spacing $::env(FP_PDN_CORE_RING_VSPACING) core_offset $::env(FP_PDN_CORE_RING_VOFFSET)}
+		$::env(FP_PDN_UPPER_LAYER) {width $::env(FP_PDN_CORE_RING_HWIDTH) spacing $::env(FP_PDN_CORE_RING_HSPACING) core_offset $::env(FP_PDN_CORE_RING_HOFFSET)}
+
+	}
+	rails {
+	}
+    straps {
+  		met4 {width $::env(FP_PDN_VWIDTH) pitch $::env(FP_PDN_VPITCH) offset $::env(FP_PDN_VOFFSET)}
+	    met5 {width $::env(FP_PDN_HWIDTH) pitch $::env(FP_PDN_HPITCH) offset $::env(FP_PDN_HOFFSET)}
+    }
+    connect {{met4 met5}}
+}
+
+set ::halo [expr min($::env(FP_HORIZONTAL_HALO), $::env(FP_VERTICAL_HALO))]
+
+# POWER or GROUND #Std. cell rails starting with power or ground rails at the bottom of the core area
+set ::rails_start_with "POWER" ;
+
+# POWER or GROUND #Upper metal stripes starting with power or ground rails at the left/bottom of the core area
+set ::stripes_start_with "POWER" ;
\ No newline at end of file
diff --git a/caravel/openlane/user_project_wrapper_empty/pin_order.cfg b/caravel/openlane/user_project_wrapper_empty/pin_order.cfg
new file mode 100644
index 0000000..90cde69
--- /dev/null
+++ b/caravel/openlane/user_project_wrapper_empty/pin_order.cfg
@@ -0,0 +1,156 @@
+#BUS_SORT
+#NR
+analog_io\[8\]
+io_in\[15\]
+io_out\[15\]
+io_oeb\[15\]
+analog_io\[9\]
+io_in\[16\]
+io_out\[16\]
+io_oeb\[16\]
+analog_io\[10\]
+io_in\[17\]
+io_out\[17\]
+io_oeb\[17\]
+analog_io\[11\]
+io_in\[18\]
+io_out\[18\]
+io_oeb\[18\]
+analog_io\[12\]
+io_in\[19\]
+io_out\[19\]
+io_oeb\[19\]
+analog_io\[13\]
+io_in\[20\]
+io_out\[20\]
+io_oeb\[20\]
+analog_io\[14\]
+io_in\[21\]
+io_out\[21\]
+io_oeb\[21\]
+analog_io\[15\]
+io_in\[22\]
+io_out\[22\]
+io_oeb\[22\]
+analog_io\[16\]
+io_in\[23\]
+io_out\[23\]
+io_oeb\[23\]
+
+#S
+wb_.*
+wbs_.*
+la_.*
+user_clock2
+user_irq.*
+
+#E
+io_in\[0\]
+io_out\[0\]
+io_oeb\[0\]
+io_in\[1\]
+io_out\[1\]
+io_oeb\[1\]
+io_in\[2\]
+io_out\[2\]
+io_oeb\[2\]
+io_in\[3\]
+io_out\[3\]
+io_oeb\[3\]
+io_in\[4\]
+io_out\[4\]
+io_oeb\[4\]
+io_in\[5\]
+io_out\[5\]
+io_oeb\[5\]
+io_in\[6\]
+io_out\[6\]
+io_oeb\[6\]
+analog_io\[0\]
+io_in\[7\]
+io_out\[7\]
+io_oeb\[7\]
+analog_io\[1\]
+io_in\[8\]
+io_out\[8\]
+io_oeb\[8\]
+analog_io\[2\]
+io_in\[9\]
+io_out\[9\]
+io_oeb\[9\]
+analog_io\[3\]
+io_in\[10\]
+io_out\[10\]
+io_oeb\[10\]
+analog_io\[4\]
+io_in\[11\]
+io_out\[11\]
+io_oeb\[11\]
+analog_io\[5\]
+io_in\[12\]
+io_out\[12\]
+io_oeb\[12\]
+analog_io\[6\]
+io_in\[13\]
+io_out\[13\]
+io_oeb\[13\]
+analog_io\[7\]
+io_in\[14\]
+io_out\[14\]
+io_oeb\[14\]
+
+#WR
+analog_io\[17\]
+io_in\[24\]
+io_out\[24\]
+io_oeb\[24\]
+analog_io\[18\]
+io_in\[25\]
+io_out\[25\]
+io_oeb\[25\]
+analog_io\[19\]
+io_in\[26\]
+io_out\[26\]
+io_oeb\[26\]
+analog_io\[20\]
+io_in\[27\]
+io_out\[27\]
+io_oeb\[27\]
+analog_io\[21\]
+io_in\[28\]
+io_out\[28\]
+io_oeb\[28\]
+analog_io\[22\]
+io_in\[29\]
+io_out\[29\]
+io_oeb\[29\]
+analog_io\[23\]
+io_in\[30\]
+io_out\[30\]
+io_oeb\[30\]
+analog_io\[24\]
+io_in\[31\]
+io_out\[31\]
+io_oeb\[31\]
+analog_io\[25\]
+io_in\[32\]
+io_out\[32\]
+io_oeb\[32\]
+analog_io\[26\]
+io_in\[33\]
+io_out\[33\]
+io_oeb\[33\]
+analog_io\[27\]
+io_in\[34\]
+io_out\[34\]
+io_oeb\[34\]
+analog_io\[28\]
+io_in\[35\]
+io_out\[35\]
+io_oeb\[35\]
+io_in\[36\]
+io_out\[36\]
+io_oeb\[36\]
+io_in\[37\]
+io_out\[37\]
+io_oeb\[37\]
diff --git a/caravel/scripts/check_density.py b/caravel/scripts/check_density.py
new file mode 100644
index 0000000..25f44ba
--- /dev/null
+++ b/caravel/scripts/check_density.py
@@ -0,0 +1,616 @@
+#!/usr/bin/env python3
+# SPDX-FileCopyrightText: 2020 Efabless Corporation
+#
+# Licensed under the Apache License, Version 2.0 (the "License");
+# you may not use this file except in compliance with the License.
+# You may obtain a copy of the License at
+#
+#      http://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing, software
+# distributed under the License is distributed on an "AS IS" BASIS,
+# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+# See the License for the specific language governing permissions and
+# limitations under the License.
+# SPDX-License-Identifier: Apache-2.0
+
+#
+# check_density.py ---
+#
+#    Run density checks on the final (filled) GDS.
+#
+
+import sys
+import os
+import re
+import select
+import subprocess
+
+def usage():
+    print("Usage:")
+    print("check_density.py [<path_to_project>] [-keep]")
+    print("")
+    print("where:")
+    print("   <path_to_project> is the path to the project top level directory.")
+    print("")
+    print("  If <path_to_project> is not given, then it is assumed to be the cwd.")
+    print("  If '-keep' is specified, then keep the check script.")
+    return 0
+
+
+if __name__ == '__main__':
+
+    optionlist = []
+    arguments = []
+
+    debugmode = False
+    keepmode = False
+
+    for option in sys.argv[1:]:
+        if option.find('-', 0) == 0:
+            optionlist.append(option)
+        else:
+            arguments.append(option)
+
+    if len(arguments) > 1:
+        print("Wrong number of arguments given to check_density.py.")
+        usage()
+        sys.exit(0)
+
+    if len(arguments) == 1:
+        user_project_path = arguments[0]
+    else:
+        user_project_path = os.getcwd()
+
+    # Check for valid user path
+
+    if not os.path.isdir(user_project_path):
+        print('Error:  Project path "' + user_project_path + '" does not exist or is not readable.')
+        sys.exit(1)
+
+    # Check for valid user ID
+    user_id_value = None
+    if os.path.isfile(user_project_path + '/info.yaml'):
+        with open(user_project_path + '/info.yaml', 'r') as ifile:
+            infolines = ifile.read().splitlines()
+            for line in infolines:
+                kvpair = line.split(':')
+                if len(kvpair) == 2:
+                    key = kvpair[0].strip()
+                    value = kvpair[1].strip()
+                    if key == 'project_id':
+                        user_id_value = value.strip('"\'')
+                        break
+
+    if user_id_value:
+        project = 'caravel'
+        project_with_id = 'caravel_' + user_id_value
+    else:
+        print('Error:  No project_id found in info.yaml file.')
+        sys.exit(1)
+
+    if '-debug' in optionlist:
+        debugmode = True
+    if '-keep' in optionlist:
+        keepmode = True
+
+    magpath = user_project_path + '/mag'
+    rcfile = magpath + '/.magicrc'
+
+    with open(magpath + '/check_density.tcl', 'w') as ofile:
+        print('#!/bin/env wish', file=ofile)
+        print('crashbackups stop', file=ofile)
+        print('drc off', file=ofile)
+        print('snap internal', file=ofile)
+
+        print('set starttime [orig_clock format [orig_clock seconds] -format "%D %T"]', file=ofile)
+        print('puts stdout "Started reading GDS: $starttime"', file=ofile)
+        print('', file=ofile)
+        print('flush stdout', file=ofile)
+        print('update idletasks', file=ofile)
+
+        # Read final project from .gds
+        print('gds readonly true', file=ofile)
+        print('gds rescale false', file=ofile)
+        print('gds read ../gds/' + project_with_id + '.gds', file=ofile)
+        print('', file=ofile)
+
+        print('set midtime [orig_clock format [orig_clock seconds] -format "%D %T"]', file=ofile)
+        print('puts stdout "Starting density checks: $midtime"', file=ofile)
+        print('', file=ofile)
+        print('flush stdout', file=ofile)
+        print('update idletasks', file=ofile)
+
+        # Get step box dimensions (700um for size and 70um for FOM step)
+        # Use 350um for stepping on other layers.
+        print('box values 0 0 0 0', file=ofile)
+        # print('box size 700um 700um', file=ofile)
+        # print('set stepbox [box values]', file=ofile)
+        # print('set stepwidth [lindex $stepbox 2]', file=ofile)
+        # print('set stepheight [lindex $stepbox 3]', file=ofile)
+
+        print('box size 70um 70um', file=ofile)
+        print('set stepbox [box values]', file=ofile)
+        print('set stepsizex [lindex $stepbox 2]', file=ofile)
+        print('set stepsizey [lindex $stepbox 3]', file=ofile)
+
+        print('select top cell', file=ofile)
+        print('expand', file=ofile)
+
+        # Modify the box to be inside the seal ring area (shrink 5um)
+        print('box grow c -5um', file=ofile)
+        print('set fullbox [box values]', file=ofile)
+
+        print('set xmax [lindex $fullbox 2]', file=ofile)
+        print('set xmin [lindex $fullbox 0]', file=ofile)
+        print('set fullwidth [expr {$xmax - $xmin}]', file=ofile)
+        print('set xtiles [expr {int(ceil(($fullwidth + 0.0) / $stepsizex))}]', file=ofile)
+        print('set ymax [lindex $fullbox 3]', file=ofile)
+        print('set ymin [lindex $fullbox 1]', file=ofile)
+        print('set fullheight [expr {$ymax - $ymin}]', file=ofile)
+        print('set ytiles [expr {int(ceil(($fullheight + 0.0) / $stepsizey))}]', file=ofile)
+        print('box size $stepsizex $stepsizey', file=ofile)
+        print('set xbase [lindex $fullbox 0]', file=ofile)
+        print('set ybase [lindex $fullbox 1]', file=ofile)
+        print('', file=ofile)
+
+        print('puts stdout "XTILES: $xtiles"', file=ofile)
+        print('puts stdout "YTILES: $ytiles"', file=ofile)
+        print('', file=ofile)
+
+        # Need to know what fraction of a full tile is the last row and column
+        print('set xfrac [expr {($xtiles * $stepsizex - $fullwidth + 0.0) / $stepsizex}]', file=ofile)
+        print('set yfrac [expr {($ytiles * $stepsizey - $fullheight + 0.0) / $stepsizey}]', file=ofile)
+        print('puts stdout "XFRAC: $xfrac"', file=ofile)
+        print('puts stdout "YFRAC: $yfrac"', file=ofile)
+
+        print('cif ostyle density', file=ofile)
+
+        # Process density at steps.  For efficiency, this is done in 70x70 um
+        # areas, dumped to a file, and then aggregated into the 700x700 areas.
+
+        print('for {set y 0} {$y < $ytiles} {incr y} {', file=ofile)
+        print('    for {set x 0} {$x < $xtiles} {incr x} {', file=ofile)
+        print('        set xlo [expr $xbase + $x * $stepsizex]', file=ofile)
+        print('        set ylo [expr $ybase + $y * $stepsizey]', file=ofile)
+        print('        set xhi [expr $xlo + $stepsizex]', file=ofile)
+        print('        set yhi [expr $ylo + $stepsizey]', file=ofile)
+        print('        box values $xlo $ylo $xhi $yhi', file=ofile)
+
+        # Flatten this area
+        print('        flatten -dobbox -nolabels tile', file=ofile)
+        print('        load tile', file=ofile)
+        print('        select top cell', file=ofile)
+
+        # Run density check for each layer
+        print('        puts stdout "Density results for tile x=$x y=$y"', file=ofile)
+
+        print('        set fdens  [cif list cover fom_all]', file=ofile)
+        print('        set pdens  [cif list cover poly_all]', file=ofile)
+        print('        set ldens  [cif list cover li_all]', file=ofile)
+        print('        set m1dens [cif list cover m1_all]', file=ofile)
+        print('        set m2dens [cif list cover m2_all]', file=ofile)
+        print('        set m3dens [cif list cover m3_all]', file=ofile)
+        print('        set m4dens [cif list cover m4_all]', file=ofile)
+        print('        set m5dens [cif list cover m5_all]', file=ofile)
+        print('        puts stdout "FOM: $fdens"', file=ofile)
+        print('        puts stdout "POLY: $pdens"', file=ofile)
+        print('        puts stdout "LI1: $ldens"', file=ofile)
+        print('        puts stdout "MET1: $m1dens"', file=ofile)
+        print('        puts stdout "MET2: $m2dens"', file=ofile)
+        print('        puts stdout "MET3: $m3dens"', file=ofile)
+        print('        puts stdout "MET4: $m4dens"', file=ofile)
+        print('        puts stdout "MET5: $m5dens"', file=ofile)
+        print('        flush stdout', file=ofile)
+        print('        update idletasks', file=ofile)
+
+        print('        load ' + project_with_id, file=ofile)
+        print('        cellname delete tile', file=ofile)
+
+        print('    }', file=ofile)
+        print('}', file=ofile)
+
+        print('set endtime [orig_clock format [orig_clock seconds] -format "%D %T"]', file=ofile)
+        print('puts stdout "Ended: $endtime"', file=ofile)
+        print('', file=ofile)
+
+
+    myenv = os.environ.copy()
+    # Real views are necessary for the DRC checks
+    myenv['MAGTYPE'] = 'mag'
+
+    print('Running density checks on file ' + project_with_id + '.gds', flush=True)
+
+    mproc = subprocess.Popen(['magic', '-dnull', '-noconsole',
+		'-rcfile', rcfile, magpath + '/check_density.tcl'],
+		stdin = subprocess.DEVNULL,
+		stdout = subprocess.PIPE,
+		stderr = subprocess.PIPE,
+		cwd = magpath,
+		env = myenv,
+		universal_newlines = True)
+
+    # Use signal to poll the process and generate any output as it arrives
+
+    dlines = []
+
+    while mproc:
+        status = mproc.poll()
+        if status != None:
+            try:
+                output = mproc.communicate(timeout=1)
+            except ValueError:
+                print('Magic forced stop, status ' + str(status))
+                sys.exit(1)
+            else:
+                outlines = output[0]
+                errlines = output[1]
+                for line in outlines.splitlines():
+                    dlines.append(line)
+                    print(line)
+                for line in errlines.splitlines():
+                    print(line)
+                print('Magic exited with status ' + str(status))
+                if int(status) != 0:
+                    sys.exit(int(status))
+                else:
+                    break
+        else:
+            n = 0
+            while True:
+                n += 1
+                if n > 100:
+                    n = 0
+                    status = mproc.poll()
+                    if status != None:
+                        break
+                sresult = select.select([mproc.stdout, mproc.stderr], [], [], 0.5)[0]
+                if mproc.stdout in sresult:
+                    outstring = mproc.stdout.readline().strip()
+                    dlines.append(outstring)
+                    print(outstring)
+                elif mproc.stderr in sresult:
+                    outstring = mproc.stderr.readline().strip()
+                    print(outstring)
+                else:
+                    break
+
+    fomfill  = []
+    polyfill = []
+    lifill   = []
+    met1fill = []
+    met2fill = []
+    met3fill = []
+    met4fill = []
+    met5fill = []
+    xtiles = 0
+    ytiles = 0
+    xfrac = 0.0
+    yfrac = 0.0
+
+    for line in dlines:
+        dpair = line.split(':')
+        if len(dpair) == 2:
+            layer = dpair[0]
+            try:
+                density = float(dpair[1].strip())
+            except:
+                continue
+            if layer == 'FOM':
+                fomfill.append(density)
+            elif layer == 'POLY':
+                polyfill.append(density)
+            elif layer == 'LI1':
+                lifill.append(density)
+            elif layer == 'MET1':
+                met1fill.append(density)
+            elif layer == 'MET2':
+                met2fill.append(density)
+            elif layer == 'MET3':
+                met3fill.append(density)
+            elif layer == 'MET4':
+                met4fill.append(density)
+            elif layer == 'MET5':
+                met5fill.append(density)
+            elif layer == 'XTILES':
+                xtiles = int(dpair[1].strip())
+            elif layer == 'YTILES':
+                ytiles = int(dpair[1].strip())
+            elif layer == 'XFRAC':
+                xfrac = float(dpair[1].strip())
+            elif layer == 'YFRAC':
+                yfrac = float(dpair[1].strip())
+
+    if ytiles == 0 or xtiles == 0:
+        print('Failed to read XTILES or YTILES from output.')
+        sys.exit(1)
+
+    total_tiles = (ytiles - 9) * (xtiles - 9)
+
+    print('')
+    print('Density results (total tiles = ' + str(total_tiles) + '):')
+
+    # For FOM, step at 70um intervals (same as 70um check area)
+    fomstep = 1
+
+    # For poly, step only at 700um intervals (10 * 70um check area)
+    polystep = 10
+
+    # For all metals, step only at 350um intervals (5 * 70um check area)
+    metalstep = 5
+
+    # Full areas are 10 x 10 tiles = 100.  But the right and top sides are
+    # not full tiles, so the full area must be prorated.
+
+    sideadjust = 90.0 + (10.0 * xfrac)
+    topadjust = 90.0 + (10.0 * yfrac)
+    corneradjust = 81.0 + (9.0 * xfrac) + (9.0 * yfrac) + (xfrac * yfrac)
+
+    print('')
+    print('FOM Density:')
+    for y in range(0, ytiles - 9, fomstep):
+        if y == ytiles - 10:
+            atotal = topadjust
+        else:
+            atotal = 100.0
+        for x in range(0, xtiles - 9, fomstep):
+            if x == xtiles - 10:
+                if y == ytiles - 10:
+                    atotal = corneradjust
+                else:
+                    atotal = sideadjust
+            fomaccum = 0
+            for w in range(y, y + 10):
+                base = xtiles * w + x
+                fomaccum += sum(fomfill[base : base + 10])
+                    
+            fomaccum /= atotal
+            print('Tile (' + str(x) + ', ' + str(y) + '):   ' + str(fomaccum))
+            if fomaccum < 0.33:
+                print('***Error:  FOM Density < 33%')
+            elif fomaccum > 0.57:
+                print('***Error:  FOM Density > 57%')
+
+    print('')
+    print('POLY Density:')
+    for y in range(0, ytiles - 9, polystep):
+        if y == ytiles - 10:
+            atotal = topadjust
+        else:
+            atotal = 100.0
+        for x in range(0, xtiles - 9, polystep):
+            if x == xtiles - 10:
+                if y == ytiles - 10:
+                    atotal = corneradjust
+                else:
+                    atotal = sideadjust
+            polyaccum = 0
+            for w in range(y, y + 10):
+                base = xtiles * w + x
+                polyaccum += sum(polyfill[base : base + 10])
+                    
+            polyaccum /= atotal
+            print('Tile (' + str(x) + ', ' + str(y) + '):   ' + str(polyaccum))
+
+    print('')
+    print('LI Density:')
+    for y in range(0, ytiles - 9, metalstep):
+        if y == ytiles - 10:
+            atotal = topadjust
+        else:
+            atotal = 100.0
+        for x in range(0, xtiles - 9, metalstep):
+            if x == xtiles - 10:
+                if y == ytiles - 10:
+                    atotal = corneradjust
+                else:
+                    atotal = sideadjust
+            liaccum = 0
+            for w in range(y, y + 10):
+                base = xtiles * w + x
+                liaccum += sum(lifill[base : base + 10])
+                    
+            liaccum /= atotal
+            print('Tile (' + str(x) + ', ' + str(y) + '):   ' + str(liaccum))
+            if liaccum < 0.35:
+                print('***Error:  LI Density < 35%')
+            elif liaccum > 0.60:
+                print('***Error:  LI Density > 60%')
+
+    print('')
+    print('MET1 Density:')
+    for y in range(0, ytiles - 9, metalstep):
+        if y == ytiles - 10:
+            atotal = topadjust
+        else:
+            atotal = 100.0
+        for x in range(0, xtiles - 9, metalstep):
+            if x == xtiles - 10:
+                if y == ytiles - 10:
+                    atotal = corneradjust
+                else:
+                    atotal = sideadjust
+            met1accum = 0
+            for w in range(y, y + 10):
+                base = xtiles * w + x
+                met1accum += sum(met1fill[base : base + 10])
+                    
+            met1accum /= atotal
+            print('Tile (' + str(x) + ', ' + str(y) + '):   ' + str(met1accum))
+            if met1accum < 0.35:
+                print('***Error:  MET1 Density < 35%')
+            elif met1accum > 0.60:
+                print('***Error:  MET1 Density > 60%')
+
+    print('')
+    print('MET2 Density:')
+    for y in range(0, ytiles - 9, metalstep):
+        if y == ytiles - 10:
+            atotal = topadjust
+        else:
+            atotal = 100.0
+        for x in range(0, xtiles - 9, metalstep):
+            if x == xtiles - 10:
+                if y == ytiles - 10:
+                    atotal = corneradjust
+                else:
+                    atotal = sideadjust
+            met2accum = 0
+            for w in range(y, y + 10):
+                base = xtiles * w + x
+                met2accum += sum(met2fill[base : base + 10])
+                    
+            met2accum /= atotal
+            print('Tile (' + str(x) + ', ' + str(y) + '):   ' + str(met2accum))
+            if met2accum < 0.35:
+                print('***Error:  MET2 Density < 35%')
+            elif met2accum > 0.60:
+                print('***Error:  MET2 Density > 60%')
+
+    print('')
+    print('MET3 Density:')
+    for y in range(0, ytiles - 9, metalstep):
+        if y == ytiles - 10:
+            atotal = topadjust
+        else:
+            atotal = 100.0
+        for x in range(0, xtiles - 9, metalstep):
+            if x == xtiles - 10:
+                if y == ytiles - 10:
+                    atotal = corneradjust
+                else:
+                    atotal = sideadjust
+            met3accum = 0
+            for w in range(y, y + 10):
+                base = xtiles * w + x
+                met3accum += sum(met3fill[base : base + 10])
+                    
+            met3accum /= atotal
+            print('Tile (' + str(x) + ', ' + str(y) + '):   ' + str(met3accum))
+            if met3accum < 0.35:
+                print('***Error:  MET3 Density < 35%')
+            elif met3accum > 0.60:
+                print('***Error:  MET3 Density > 60%')
+
+    print('')
+    print('MET4 Density:')
+    for y in range(0, ytiles - 9, metalstep):
+        if y == ytiles - 10:
+            atotal = topadjust
+        else:
+            atotal = 100.0
+        for x in range(0, xtiles - 9, metalstep):
+            if x == xtiles - 10:
+                if y == ytiles - 10:
+                    atotal = corneradjust
+                else:
+                    atotal = sideadjust
+            met4accum = 0
+            for w in range(y, y + 10):
+                base = xtiles * w + x
+                met4accum += sum(met4fill[base : base + 10])
+                    
+            met4accum /= atotal
+            print('Tile (' + str(x) + ', ' + str(y) + '):   ' + str(met4accum))
+            if met4accum < 0.35:
+                print('***Error:  MET4 Density < 35%')
+            elif met4accum > 0.60:
+                print('***Error:  MET4 Density > 60%')
+
+    print('')
+    print('MET5 Density:')
+    for y in range(0, ytiles - 9, metalstep):
+        if y == ytiles - 10:
+            atotal = topadjust
+        else:
+            atotal = 100.0
+        for x in range(0, xtiles - 9, metalstep):
+            if x == xtiles - 10:
+                if y == ytiles - 10:
+                    atotal = corneradjust
+                else:
+                    atotal = sideadjust
+            met5accum = 0
+            for w in range(y, y + 10):
+                base = xtiles * w + x
+                met5accum += sum(met5fill[base : base + 10])
+                    
+            met5accum /= atotal
+            print('Tile (' + str(x) + ', ' + str(y) + '):   ' + str(met5accum))
+            if met5accum < 0.45:
+                print('***Error:  MET5 Density < 45%')
+            elif met5accum > 0.76:
+                print('***Error:  MET5 Density > 76%')
+
+    print('')
+    print('Whole-chip density results:')
+
+    atotal = ((xtiles - 1.0) * (ytiles - 1.0)) + ((ytiles - 1.0) * xfrac) + ((xtiles - 1.0) * yfrac) + (xfrac * yfrac)
+
+    fomaccum = sum(fomfill) / atotal
+    print('')
+    print('FOM Density: ' + str(fomaccum))
+    if fomaccum < 0.33:
+        print('***Error:  FOM Density < 33%')
+    elif fomaccum > 0.57:
+        print('***Error:  FOM Density > 57%')
+
+    polyaccum = sum(polyfill) / atotal
+    print('')
+    print('POLY Density: ' + str(polyaccum))
+
+    liaccum = sum(lifill) / atotal
+    print('')
+    print('LI Density: ' + str(liaccum))
+    if liaccum < 0.35:
+        print('***Error:  LI Density < 35%')
+    elif liaccum > 0.60:
+        print('***Error:  LI Density > 60%')
+
+    met1accum = sum(met1fill) / atotal
+    print('')
+    print('MET1 Density: ' + str(met1accum))
+    if met1accum < 0.35:
+        print('***Error:  MET1 Density < 35%')
+    elif met1accum > 0.60:
+        print('***Error:  MET1 Density > 60%')
+
+    met2accum = sum(met2fill) / atotal
+    print('')
+    print('MET2 Density: ' + str(met2accum))
+    if met2accum < 0.35:
+        print('***Error:  MET2 Density < 35%')
+    elif met2accum > 0.60:
+        print('***Error:  MET2 Density > 60%')
+
+    met3accum = sum(met3fill) / atotal
+    print('')
+    print('MET3 Density: ' + str(met3accum))
+    if met3accum < 0.35:
+        print('***Error:  MET3 Density < 35%')
+    elif met3accum > 0.60:
+        print('***Error:  MET3 Density > 60%')
+
+    met4accum = sum(met4fill) / atotal
+    print('')
+    print('MET4 Density: ' + str(met4accum))
+    if met4accum < 0.35:
+        print('***Error:  MET4 Density < 35%')
+    elif met4accum > 0.60:
+        print('***Error:  MET4 Density > 60%')
+
+    met5accum = sum(met5fill) / atotal
+    print('')
+    print('MET5 Density: ' + str(met5accum))
+    if met5accum < 0.45:
+        print('***Error:  MET5 Density < 45%')
+    elif met5accum > 0.76:
+        print('***Error:  MET5 Density > 76%')
+
+    if not keepmode:
+        if os.path.isfile(magpath + '/check_density.tcl'):
+            os.remove(magpath + '/check_density.tcl')
+
+    print('')
+    print('Done!')
+    sys.exit(0)
diff --git a/caravel/scripts/compositor.py b/caravel/scripts/compositor.py
new file mode 100644
index 0000000..8e6ceb5
--- /dev/null
+++ b/caravel/scripts/compositor.py
@@ -0,0 +1,246 @@
+#!/usr/bin/env python3
+# SPDX-FileCopyrightText: 2020 Efabless Corporation
+#
+# Licensed under the Apache License, Version 2.0 (the "License");
+# you may not use this file except in compliance with the License.
+# You may obtain a copy of the License at
+#
+#      http://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing, software
+# distributed under the License is distributed on an "AS IS" BASIS,
+# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+# See the License for the specific language governing permissions and
+# limitations under the License.
+# SPDX-License-Identifier: Apache-2.0
+
+#
+# compositor.py ---
+#
+#    Compose the final GDS for caravel from the caravel GDS, seal ring
+#    GDS, and fill GDS.
+#
+
+import sys
+import os
+import re
+import subprocess
+
+def usage():
+    print("Usage:")
+    print("compositor.py [<user_id_value>] [<path_to_project>] [<path_to_mag_dir>] [<path_to_gds_dir] [-keep]")
+    print("")
+    print("where:")
+    print("   <user_id_value>   is a character string of eight hex digits, and")
+    print("   <path_to_project> is the path to the project top level directory.")
+    print("   <path_to_mag_dir> is the path to the mag directory.")
+    print("   <path_to_gds_dir> is the path to the gds directory.")
+    print("")
+    print("  If <user_id_value> is not given, then it must exist in the info.yaml file.")
+    print("  If <path_to_project> is not given, then it is assumed to be the cwd.")
+    print("  If <path_to_mag_dir> is not given, then it is assumed to be the <path_to_project>/tmp.")
+    print("  If <path_to_gds_dir> is not given, then it is assumed to be the <path_to_project>/gds.")
+    print("  If '-keep' is specified, then keep the generation script.")
+    return 0
+
+if __name__ == '__main__':
+
+    optionlist = []
+    arguments = []
+
+    debugmode = False
+    keepmode = False
+
+    for option in sys.argv[1:]:
+        if option.find('-', 0) == 0:
+            optionlist.append(option)
+        else:
+            arguments.append(option)
+
+    if len(arguments) > 4:
+        print("Wrong number of arguments given to compositor.py.")
+        usage()
+        sys.exit(0)
+
+    user_id_value = None
+    if len(arguments) > 0:
+        user_id_value = arguments[0]
+
+        # Convert to binary
+        try:
+            user_id_int = int('0x' + user_id_value, 0)
+            user_id_bits = '{0:032b}'.format(user_id_int)
+        except:
+            user_project_path = arguments[0]
+            user_id_value = None
+
+    if len(arguments) == 2 and user_project_path == None:
+        user_project_path = arguments[1]
+        mag_dir_path = user_project_path + "/mag"
+        gds_dir_path = "../gds"
+    if len(arguments) == 3 and user_project_path == None:
+        user_project_path = arguments[1]
+        mag_dir_path = arguments[2]
+        gds_dir_path = "../gds"
+    if len(arguments) == 4:
+        user_project_path = arguments[1]
+        mag_dir_path = arguments[2]
+        gds_dir_path =  arguments[3]
+    elif len(arguments) == 3 and user_project_path != None:
+        mag_dir_path = arguments[1]
+        gds_dir_path =  arguments[2]
+    else:
+        user_project_path = os.getcwd()
+        mag_dir_path = user_project_path + "/mag"
+        gds_dir_path = "../gds"
+
+    # Check for valid user path
+
+    if not os.path.isdir(user_project_path):
+        print('Error:  Project path "' + user_project_path + '" does not exist or is not readable.')
+        sys.exit(1)
+
+    # Check for valid mag path
+
+    if not os.path.isdir(mag_dir_path):
+        print('Error:  Mag directory path "' + mag_dir_path + '" does not exist or is not readable.')
+        sys.exit(1)
+
+    # Check for valid gds path
+
+    if not os.path.isdir(gds_dir_path):
+        print('Error:  GDS directory path "' + gds_dir_path + '" does not exist or is not readable.')
+        sys.exit(1)
+
+    # Check for valid user ID
+    if not user_id_value:
+        if os.path.isfile(user_project_path + '/info.yaml'):
+            with open(user_project_path + '/info.yaml', 'r') as ifile:
+                infolines = ifile.read().splitlines()
+                for line in infolines:
+                    kvpair = line.split(':')
+                    if len(kvpair) == 2:
+                        key = kvpair[0].strip()
+                        value = kvpair[1].strip()
+                        if key == 'project_id':
+                            user_id_value = value.strip('"\'')
+                            break
+
+    if user_id_value:
+        project = 'caravel'
+        project_with_id = 'caravel_' + user_id_value
+        user_id_decimal = str(int(user_id_value, 16))
+    else:
+        print('Error:  No project_id found in info.yaml file.')
+        sys.exit(1)
+
+    if '-debug' in optionlist:
+        debugmode = True
+    if '-keep' in optionlist:
+        keepmode = True
+
+    magpath = mag_dir_path
+    rcfile = magpath + '/.magicrc'
+
+    gdspath = gds_dir_path
+
+    # The compositor script will create <project_with_id>.mag, but is uses
+    # "load", so the file must not already exist.
+
+    if os.path.isfile(magpath + '/' + project_with_id + '.mag'):
+        print('Error:  File ' + project_with_id + '.mag exists already!  Exiting. . .')
+        sys.exit(1)
+
+    with open(magpath + '/compose_final.tcl', 'w') as ofile:
+        print('#!/bin/env wish', file=ofile)
+        print('drc off', file=ofile)
+        # Set the random seed from the project ID
+        print('random seed ' + user_id_decimal, file=ofile)
+
+        # Read project from .mag but set GDS properties so that it points
+        # to the GDS file created by "make ship".
+        print('load ' + project + ' -dereference', file=ofile)
+        print('property GDS_FILE ' + gdspath + '/' + project + '.gds', file=ofile)
+        print('property GDS_START 0', file=ofile)
+        print('select top cell', file=ofile)
+        print('set bbox [box values]', file=ofile)
+
+        # Ceate a cell to represent the generated fill.  There are
+        # no magic layers corresponding to the fill shape data, and
+        # it's gigabytes anyway, so we don't want to deal with any
+        # actual data.  So it's just a placeholder.
+
+        print('load ' + project_with_id + '_fill_pattern -quiet', file=ofile)
+        print('snap internal', file=ofile)
+        print('box values {*}$bbox', file=ofile)
+        print('paint comment', file=ofile)
+        print('property GDS_FILE ' + gdspath + '/' + project_with_id + '_fill_pattern.gds', file=ofile)
+        print('property GDS_START 0', file=ofile)
+        print('property FIXED_BBOX "$bbox"', file=ofile)
+
+        # Create a new project top level and place the fill cell.
+        print('load ' + project_with_id + ' -quiet', file=ofile)
+        print('box values 0 0 0 0', file=ofile)	
+        print('box position 6um 6um', file=ofile)	
+        print('getcell ' + project + ' child 0 0', file=ofile)
+        print('getcell ' + project_with_id + '_fill_pattern child 0 0', file=ofile)
+
+        # Move existing origin to (6um, 6um) for seal ring placement
+        # print('move origin -6um -6um', file=ofile)
+
+        # Read in abstract view of seal ring
+        print('box position 0 0', file=ofile)
+        print('getcell advSeal_6um_gen', file=ofile)
+
+        # Write out completed project as "caravel_" + the user ID
+        print('save ' + project_with_id, file=ofile)
+
+        # Generate final GDS
+        print('puts stdout "Writing final GDS. . . "', file=ofile)
+        print('flush stdout', file=ofile)
+        print('gds undefined allow', file=ofile)
+        print('cif *hier write disable', file=ofile)
+        print('gds write ' + gdspath + '/' + project_with_id + '.gds', file=ofile)
+        print('quit -noprompt', file=ofile)
+
+    myenv = os.environ.copy()
+    # Abstract views are appropriate for final composition
+    myenv['MAGTYPE'] = 'maglef'
+
+    print('Building final GDS file ' + project_with_id + '.gds', flush=True)
+
+    mproc = subprocess.run(['magic', '-dnull', '-noconsole',
+		'-rcfile', rcfile, magpath + '/compose_final.tcl'],
+		stdin = subprocess.DEVNULL,
+		stdout = subprocess.PIPE,
+		stderr = subprocess.PIPE,
+		cwd = magpath,
+		env = myenv,
+		universal_newlines = True)
+    if mproc.stdout:
+        for line in mproc.stdout.splitlines():
+            print(line)
+    if mproc.stderr:
+        # NOTE:  Until there is a "load -quiet" option in magic, loading
+        # a new cell generates an error.  This code ignores the error.
+        newlines = []
+        for line in mproc.stderr.splitlines():
+            if line.endswith("_fill_pattern.mag couldn't be read"):
+                continue
+            if line.startswith("No such file or directory"):
+                continue
+            else:
+                newlines.append(line)
+
+        if len(newlines) > 0:
+            print('Error message output from magic:')
+            for line in newlines:
+                print(line)
+        if mproc.returncode != 0:
+            print('ERROR:  Magic exited with status ' + str(mproc.returncode))
+
+    if not keepmode:
+        os.remove(magpath + '/compose_final.tcl')
+
+    print('Done!')
+    exit(0)
diff --git a/caravel/scripts/count_lvs.py b/caravel/scripts/count_lvs.py
new file mode 100644
index 0000000..21b7771
--- /dev/null
+++ b/caravel/scripts/count_lvs.py
@@ -0,0 +1,132 @@
+#!/usr/bin/python3
+# SPDX-FileCopyrightText: 2020 Efabless Corporation
+#
+# Licensed under the Apache License, Version 2.0 (the "License");
+# you may not use this file except in compliance with the License.
+# You may obtain a copy of the License at
+#
+#      http://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing, software
+# distributed under the License is distributed on an "AS IS" BASIS,
+# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+# See the License for the specific language governing permissions and
+# limitations under the License.
+# SPDX-License-Identifier: Apache-2.0
+
+#
+#---------------------------------------------------------
+# LVS failure check
+#
+# This is a Python script that parses the comp.json
+# output from netgen and reports on the number of
+# errors in the top-level netlist.
+#
+#---------------------------------------------------------
+# Written by Tim Edwards
+# efabless, inc.
+# Pulled from qflow GUI as standalone script Aug 20, 2018
+#---------------------------------------------------------
+
+import os
+import re
+import sys
+import json
+import argparse
+
+def count_LVS_failures(filename):
+    with open(filename, 'r') as cfile:
+        lvsdata = json.load(cfile)
+
+    # Count errors in the JSON file
+    failures = 0
+    devfail = 0
+    netfail = 0
+    pinfail = 0
+    propfail = 0
+    netdiff = 0
+    devdiff = 0
+    ncells = len(lvsdata)
+    for c in range(0, ncells):
+        cellrec = lvsdata[c]
+
+        if c == ncells - 1:
+            topcell = True
+        else:
+            topcell = False
+
+        # Most errors must only be counted for the top cell, because individual
+        # failing cells are flattened and the matching attempted again on the
+        # flattened netlist.
+
+        if topcell:
+            if 'devices' in cellrec:
+                devices = cellrec['devices']
+                devlist = [val for pair in zip(devices[0], devices[1]) for val in pair]
+                devpair = list(devlist[p:p + 2] for p in range(0, len(devlist), 2))
+                for dev in devpair:
+                    c1dev = dev[0]
+                    c2dev = dev[1]
+                    diffdevs = abs(c1dev[1] - c2dev[1])
+                    failures += diffdevs
+                    devdiff += diffdevs
+
+            if 'nets' in cellrec:
+                nets = cellrec['nets']
+                diffnets = abs(nets[0] - nets[1])
+                failures += diffnets
+                netdiff += diffnets
+
+            if 'badnets' in cellrec:
+                badnets = cellrec['badnets']
+                failures += len(badnets)
+                netfail += len(badnets)
+
+            if 'badelements' in cellrec:
+                badelements = cellrec['badelements']
+                failures += len(badelements)
+                devfail += len(badelements)
+
+            if 'pins' in cellrec:
+                pins = cellrec['pins']
+                pinlist = [val for pair in zip(pins[0], pins[1]) for val in pair]
+                pinpair = list(pinlist[p:p + 2] for p in range(0, len(pinlist), 2))
+                for pin in pinpair:
+                    # Avoid flagging global vs. local names, e.g., "gnd" vs. "gnd!,"
+                    # and ignore case when comparing pins.
+                    pin0 = re.sub('!$', '', pin[0].lower())
+                    pin1 = re.sub('!$', '', pin[1].lower())
+                    if pin0 != pin1:
+                        failures += 1
+                        pinfail += 1
+
+        # Property errors must be counted for every cell
+        if 'properties' in cellrec:
+            properties = cellrec['properties']
+            failures += len(properties)
+            propfail += len(properties)
+
+    return [failures, netfail, devfail, pinfail, propfail, netdiff, devdiff]
+
+if __name__ == '__main__':
+
+    parser = argparse.ArgumentParser(description='Parses netgen lvs')
+    parser.add_argument('--file', '-f', required=True)
+    args = parser.parse_args()
+    failures = count_LVS_failures(args.file)
+    total = failures[0]
+    if total > 0:
+        failed = True
+        print('LVS reports:')
+        print('    net count difference = ' + str(failures[5]))
+        print('    device count difference = ' + str(failures[6]))
+        print('    unmatched nets = ' + str(failures[1]))
+        print('    unmatched devices = ' + str(failures[2]))
+        print('    unmatched pins = ' + str(failures[3]))
+        print('    property failures = ' + str(failures[4]))
+    else:
+        print('LVS reports no net, device, pin, or property mismatches.')
+
+    print('')
+    print('Total errors = ' + str(total))
+ 
diff --git a/caravel/scripts/create-caravel-diagram.py b/caravel/scripts/create-caravel-diagram.py
new file mode 100644
index 0000000..bfb4e3c
--- /dev/null
+++ b/caravel/scripts/create-caravel-diagram.py
@@ -0,0 +1,126 @@
+# SPDX-FileCopyrightText: 2020 Efabless Corporation
+#
+# Licensed under the Apache License, Version 2.0 (the "License");
+# you may not use this file except in compliance with the License.
+# You may obtain a copy of the License at
+#
+#      http://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing, software
+# distributed under the License is distributed on an "AS IS" BASIS,
+# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+# See the License for the specific language governing permissions and
+# limitations under the License.
+# SPDX-License-Identifier: Apache-2.0
+import sys
+import os
+import subprocess
+from pathlib import Path
+import argparse
+from tempfile import mkstemp
+import re
+
+
+def remove_inouts(jsonpath, replacewith='input'):
+    """Replaces inouts with either input or output statements.
+
+    Netlistsvg does not parse inout ports as for now, so they need to be
+    replaced with either input or output to produce a diagram.
+
+    Parameters
+    ----------
+    jsonpath : str
+        Path to JSON file to fix
+    replacewith : str
+        The string to replace 'inout', can be 'input' or 'output'
+    """
+    assert replacewith in ['input', 'output']
+    with open(jsonpath, 'r') as withinouts:
+        lines = withinouts.readlines()
+    with open(jsonpath, 'w') as withoutinouts:
+        for line in lines:
+            withoutinouts.write(re.sub('inout', replacewith, line))
+
+
+def main(argv):
+    parser = argparse.ArgumentParser(argv[0])
+    parser.add_argument(
+        'verilog_rtl_dir',
+        help="Path to the project's verilog/rtl directory",
+        type=Path)
+    parser.add_argument(
+        'output',
+        help="Path to the output SVG file",
+        type=Path)
+    parser.add_argument(
+        '--num-iopads',
+        help='Number of iopads to render',
+        type=int,
+        default=38)
+    parser.add_argument(
+        '--yosys-executable',
+        help='Path to yosys executable',
+        type=Path,
+        default='yosys')
+    parser.add_argument(
+        '--netlistsvg-executable',
+        help='Path to netlistsvg executable',
+        type=Path,
+        default='netlistsvg')
+    parser.add_argument(
+        '--inouts-as',
+        help='To what kind of IO should inout ports be replaced',
+        choices=['input', 'output'],
+        default='input'
+    )
+
+    args = parser.parse_args(argv[1:])
+
+    fd, jsonpath = mkstemp(suffix='-yosys.json')
+    os.close(fd)
+
+    yosyscommand = [
+        f'{str(args.yosys_executable)}',
+        '-p',
+        'read_verilog pads.v defines.v; ' +
+        'read_verilog -lib -overwrite *.v; ' +
+        f'verilog_defines -DMPRJ_IO_PADS={args.num_iopads}; ' +
+        'read_verilog -overwrite caravel.v; ' +
+        'hierarchy -top caravel; ' +
+        'proc; ' +
+        'opt; ' +
+        f'write_json {jsonpath}; '
+    ]
+
+    result = subprocess.run(
+        yosyscommand,
+        cwd=args.verilog_rtl_dir,
+        stdout=subprocess.PIPE,
+        stderr=subprocess.STDOUT
+    )
+
+    exitcode = 0
+    if result.returncode != 0:
+        print(f'Failed to run: {" ".join(yosyscommand)}', file=sys.stderr)
+        print(result.stdout.decode())
+        exitcode = result.returncode
+    else:
+        # TODO once netlistsvg supports inout ports, this should be removed
+        remove_inouts(jsonpath, args.inouts_as)
+        command = f'{args.netlistsvg_executable} {jsonpath} -o {args.output}'
+        result = subprocess.run(
+            command.split(),
+            stdout=subprocess.PIPE,
+            stderr=subprocess.STDOUT
+        )
+        if result.returncode != 0:
+            print(f'Failed to run: {command}', file=sys.stderr)
+            print(result.stdout.decode())
+            exitcode = result.returncode
+
+    os.unlink(jsonpath)
+    sys.exit(exitcode)
+
+
+if __name__ == '__main__':
+    sys.exit(main(sys.argv))
diff --git a/caravel/scripts/generate_fill.py b/caravel/scripts/generate_fill.py
new file mode 100644
index 0000000..d12024a
--- /dev/null
+++ b/caravel/scripts/generate_fill.py
@@ -0,0 +1,415 @@
+#!/usr/bin/env python3
+# SPDX-FileCopyrightText: 2020 Efabless Corporation
+#
+# Licensed under the Apache License, Version 2.0 (the "License");
+# you may not use this file except in compliance with the License.
+# You may obtain a copy of the License at
+#
+#      http://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing, software
+# distributed under the License is distributed on an "AS IS" BASIS,
+# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+# See the License for the specific language governing permissions and
+# limitations under the License.
+# SPDX-License-Identifier: Apache-2.0
+
+#
+# generate_fill.py ---
+#
+#    Run the fill generation on a layout top level.
+#
+
+import sys
+import os
+import re
+import glob
+import subprocess
+import multiprocessing
+
+def usage():
+    print("Usage:")
+    print("generate_fill.py [<user_id_value>] [<path_to_project>] [-keep] [-test] [-dist]")
+    print("")
+    print("where:")
+    print("    <user_id_value>   is a character string of eight hex digits, and")
+    print("    <path_to_project> is the path to the project top level directory.")
+    print("")
+    print("  If <user_id_value> is not given, then it must exist in the info.yaml file.")
+    print("  If <path_to_project> is not given, then it is assumed to be the cwd.")
+    print("  If '-keep' is specified, then keep the generation script.")
+    print("  If '-test' is specified, then create but do not run the generation script.")
+    print("  If '-dist' is specified, then run distributed (multi-processing).")
+
+    return 0
+
+def makegds(file):
+    # Procedure for multiprocessing run only:  Run the distributed processing
+    # script to load a .mag file of one flattened square area of the layout,
+    # and run the fill generator to produce a .gds file output from it.
+
+    magpath = os.path.split(file)[0]
+    filename = os.path.split(file)[1]
+
+    myenv = os.environ.copy()
+    myenv['MAGTYPE'] = 'mag'
+
+    mproc = subprocess.run(['magic', '-dnull', '-noconsole',
+		'-rcfile', rcfile, magpath + '/generate_fill_dist.tcl',
+		filename],
+		stdin = subprocess.DEVNULL,
+		stdout = subprocess.PIPE,
+		stderr = subprocess.PIPE,
+		cwd = magpath,
+		env = myenv,
+		universal_newlines = True)
+    if mproc.stdout:
+        for line in mproc.stdout.splitlines():
+            print(line)
+    if mproc.stderr:
+        print('Error message output from magic:')
+        for line in mproc.stderr.splitlines():
+            print(line)
+        if mproc.returncode != 0:
+            print('ERROR:  Magic exited with status ' + str(mproc.returncode))
+
+
+if __name__ == '__main__':
+
+    optionlist = []
+    arguments = []
+
+    debugmode = False
+    keepmode = False
+    testmode = False
+    distmode = False
+
+    for option in sys.argv[1:]:
+        if option.find('-', 0) == 0:
+            optionlist.append(option)
+        else:
+            arguments.append(option)
+
+    if len(arguments) > 2:
+        print("Wrong number of arguments given to generate_fill.py.")
+        usage()
+        sys.exit(1)
+
+    user_id_value = None
+    user_project_path = None
+    
+    if len(arguments) > 0:
+        user_id_value = arguments[0]
+
+        # Convert to binary
+        try:
+            user_id_int = int('0x' + user_id_value, 0)
+            user_id_bits = '{0:032b}'.format(user_id_int)
+        except:
+            user_project_path = arguments[0]
+
+    if len(arguments) == 0:
+        user_project_path = os.getcwd() 
+    elif len(arguments) == 2:
+        user_project_path = arguments[1]
+    elif user_project_path == None:
+        user_project_path = arguments[0]
+    else:
+        user_project_path = os.getcwd()
+
+    if not os.path.isdir(user_project_path):
+        print('Error:  Project path "' + user_project_path + '" does not exist or is not readable.')
+        sys.exit(1)
+
+    # Check for valid user ID
+    if not user_id_value:
+        if os.path.isfile(user_project_path + '/info.yaml'):
+            with open(user_project_path + '/info.yaml', 'r') as ifile:
+                infolines = ifile.read().splitlines()
+                for line in infolines:
+                    kvpair = line.split(':')
+                    if len(kvpair) == 2:
+                        key = kvpair[0].strip()
+                        value = kvpair[1].strip()
+                        if key == 'project_id':
+                            user_id_value = value.strip('"\'')
+                            break
+
+    project = 'caravel'
+    if user_id_value:
+        project_with_id = project + '_' + user_id_value
+    else:
+        print('Error:  No project_id found in info.yaml file.')
+        sys.exit(1)
+
+    if '-debug' in optionlist:
+        debugmode = True
+    if '-keep' in optionlist:
+        keepmode = True
+    if '-test' in optionlist:
+        testmode = True
+    if '-dist' in optionlist:
+        distmode = True
+
+    magpath = user_project_path + '/mag'
+    rcfile = magpath + '/.magicrc'
+
+    if not os.path.isfile(rcfile):
+        rcfile = None
+
+    topdir = user_project_path
+    gdsdir = topdir + '/gds'
+    hasgdsdir = True if os.path.isdir(gdsdir) else False
+
+    ofile = open(magpath + '/generate_fill.tcl', 'w')
+
+    print('#!/bin/env wish', file=ofile)
+    print('drc off', file=ofile)
+    print('tech unlock *', file=ofile)
+    print('snap internal', file=ofile)
+    print('box values 0 0 0 0', file=ofile)
+    print('box size 700um 700um', file=ofile)
+    print('set stepbox [box values]', file=ofile)
+    print('set stepwidth [lindex $stepbox 2]', file=ofile)
+    print('set stepheight [lindex $stepbox 3]', file=ofile)
+    print('', file=ofile)
+    print('set starttime [orig_clock format [orig_clock seconds] -format "%D %T"]', file=ofile)
+    print('puts stdout "Started: $starttime"', file=ofile)
+    print('', file=ofile)
+    # Read the user project from GDS, as there is not necessarily a magic database file
+    # to go along with this.
+    # print('gds read ../gds/user_project_wrapper', file=ofile)
+    # Now read the full caravel project
+    # print('load ' + project + ' -dereference', file=ofile)
+    print('gds readonly true', file=ofile)
+    print('gds rescale false', file=ofile)
+    print('gds read ../gds/caravel', file=ofile)
+    print('select top cell', file=ofile)
+    print('expand', file=ofile)
+    if not distmode:
+        print('cif ostyle wafflefill(tiled)', file=ofile)
+    print('', file=ofile)
+    print('set fullbox [box values]', file=ofile)
+    print('set xmax [lindex $fullbox 2]', file=ofile)
+    print('set xmin [lindex $fullbox 0]', file=ofile)
+    print('set fullwidth [expr {$xmax - $xmin}]', file=ofile)
+    print('set xtiles [expr {int(ceil(($fullwidth + 0.0) / $stepwidth))}]', file=ofile)
+    print('set ymax [lindex $fullbox 3]', file=ofile)
+    print('set ymin [lindex $fullbox 1]', file=ofile)
+    print('set fullheight [expr {$ymax - $ymin}]', file=ofile)
+    print('set ytiles [expr {int(ceil(($fullheight + 0.0) / $stepheight))}]', file=ofile)
+    print('box size $stepwidth $stepheight', file=ofile)
+    print('set xbase [lindex $fullbox 0]', file=ofile)
+    print('set ybase [lindex $fullbox 1]', file=ofile)
+    print('', file=ofile)
+
+    # Break layout into tiles and process each separately
+    print('for {set y 0} {$y < $ytiles} {incr y} {', file=ofile)
+    print('    for {set x 0} {$x < $xtiles} {incr x} {', file=ofile)
+    print('        set xlo [expr $xbase + $x * $stepwidth]', file=ofile)
+    print('        set ylo [expr $ybase + $y * $stepheight]', file=ofile)
+    print('        set xhi [expr $xlo + $stepwidth]', file=ofile)
+    print('        set yhi [expr $ylo + $stepheight]', file=ofile)
+    print('        if {$xhi > $fullwidth} {set xhi $fullwidth}', file=ofile)
+    print('        if {$yhi > $fullheight} {set yhi $fullheight}', file=ofile)
+    print('        box values $xlo $ylo $xhi $yhi', file=ofile)
+    # The flattened area must be larger than the fill tile by >1.5um
+    print('        box grow c 1.6um', file=ofile)
+
+    # Flatten into a cell with a new name
+    print('        puts stdout "Flattening layout of tile x=$x y=$y. . . "', file=ofile)
+    print('        flush stdout', file=ofile)
+    print('        update idletasks', file=ofile)
+    print('        flatten -dobox -nolabels ' + project_with_id + '_fill_pattern_${x}_$y', file=ofile)
+    print('        load ' + project_with_id + '_fill_pattern_${x}_$y', file=ofile)
+    # Remove any GDS_FILE reference (there should not be any?)
+    print('        property GDS_FILE ""', file=ofile)
+    # Set boundary using comment layer, to the size of the step box
+    # This corresponds to the "topbox" rule in the wafflefill(tiled) style
+    print('        select top cell', file=ofile)
+    print('        erase comment', file=ofile)
+    print('        box values $xlo $ylo $xhi $yhi', file=ofile)
+    print('        paint comment', file=ofile)
+
+    if not distmode:
+        print('        puts stdout "Writing GDS. . . "', file=ofile)
+
+    print('        flush stdout', file=ofile)
+    print('        update idletasks', file=ofile)
+
+    if distmode:
+        print('        writeall force ' + project_with_id + '_fill_pattern_${x}_$y', file=ofile)
+    else:
+        print('        gds write ' + project_with_id + '_fill_pattern_${x}_$y.gds', file=ofile)
+    # Reload project top
+    print('        load ' + project, file=ofile)
+
+    # Remove last generated cell to save memory
+    print('        cellname delete ' + project_with_id + '_fill_pattern_${x}_$y', file=ofile)
+
+    print('    }', file=ofile)
+    print('}', file=ofile)
+
+    if distmode:
+        print('set ofile [open fill_gen_info.txt w]', file=ofile)
+        print('puts $ofile "$stepwidth"', file=ofile)
+        print('puts $ofile "$stepheight"', file=ofile)
+        print('puts $ofile "$xtiles"', file=ofile)
+        print('puts $ofile "$ytiles"', file=ofile)
+        print('puts $ofile "$xbase"', file=ofile)
+        print('puts $ofile "$ybase"', file=ofile)
+        print('close $ofile', file=ofile)
+        print('quit -noprompt', file=ofile)
+        ofile.close()
+
+        with open(magpath + '/generate_fill_dist.tcl', 'w') as ofile:
+            print('#!/bin/env wish', file=ofile)
+            print('drc off', file=ofile)
+            print('tech unlock *', file=ofile)
+            print('snap internal', file=ofile)
+            print('box values 0 0 0 0', file=ofile)
+            print('set filename [file root [lindex $argv $argc-1]]', file=ofile)
+            print('load $filename', file=ofile)
+            print('cif ostyle wafflefill(tiled)', file=ofile)
+            print('gds write [file root $filename].gds', file=ofile)
+            print('quit -noprompt', file=ofile)
+
+        ofile = open(magpath + '/generate_fill_final.tcl', 'w')
+        print('#!/bin/env wish', file=ofile)
+        print('drc off', file=ofile)
+        print('tech unlock *', file=ofile)
+        print('snap internal', file=ofile)
+        print('box values 0 0 0 0', file=ofile)
+
+        print('set ifile [open fill_gen_info.txt r]', file=ofile)
+        print('gets $ifile stepwidth', file=ofile)
+        print('gets $ifile stepheight', file=ofile)
+        print('gets $ifile xtiles', file=ofile)
+        print('gets $ifile ytiles', file=ofile)
+        print('gets $ifile xbase', file=ofile)
+        print('gets $ifile ybase', file=ofile)
+        print('close $ifile', file=ofile)
+        print('cif ostyle wafflefill(tiled)', file=ofile)
+
+    # Now create simple "fake" views of all the tiles.
+    print('gds readonly true', file=ofile)
+    print('gds rescale false', file=ofile)
+    print('for {set y 0} {$y < $ytiles} {incr y} {', file=ofile)
+    print('    for {set x 0} {$x < $xtiles} {incr x} {', file=ofile)
+    print('        set xlo [expr $xbase + $x * $stepwidth]', file=ofile)
+    print('        set ylo [expr $ybase + $y * $stepheight]', file=ofile)
+    print('        set xhi [expr $xlo + $stepwidth]', file=ofile)
+    print('        set yhi [expr $ylo + $stepheight]', file=ofile)
+    print('        load ' + project_with_id + '_fill_pattern_${x}_$y -quiet', file=ofile)
+    print('        box values $xlo $ylo $xhi $yhi', file=ofile)
+    print('        paint comment', file=ofile)
+    print('        property FIXED_BBOX "$xlo $ylo $xhi $yhi"', file=ofile)
+    print('        property GDS_FILE ' + project_with_id + '_fill_pattern_${x}_${y}.gds', file=ofile)
+    print('        property GDS_START 0', file=ofile)
+    print('    }', file=ofile)
+    print('}', file=ofile)
+
+    # Now tile everything back together
+    print('load ' + project_with_id + '_fill_pattern -quiet', file=ofile)
+    print('for {set y 0} {$y < $ytiles} {incr y} {', file=ofile)
+    print('    for {set x 0} {$x < $xtiles} {incr x} {', file=ofile)
+    print('        box values 0 0 0 0', file=ofile)
+    print('        getcell ' + project_with_id + '_fill_pattern_${x}_$y child 0 0', file=ofile)
+    print('    }', file=ofile)
+    print('}', file=ofile)
+
+    # And write final GDS
+    print('puts stdout "Writing final GDS"', file=ofile)
+
+    print('cif *hier write disable', file=ofile)
+    print('cif *array write disable', file=ofile)
+    if hasgdsdir:
+        print('gds write ../gds/' + project_with_id + '_fill_pattern.gds', file=ofile)
+    else:
+        print('gds write ' + project_with_id + '_fill_pattern.gds', file=ofile)
+    print('set endtime [orig_clock format [orig_clock seconds] -format "%D %T"]', file=ofile)
+    print('puts stdout "Ended: $endtime"', file=ofile)
+    print('quit -noprompt', file=ofile)
+    ofile.close()
+
+    myenv = os.environ.copy()
+    myenv['MAGTYPE'] = 'mag'
+
+    if not testmode:
+        # Diagnostic
+        # print('This script will generate file ' + project_with_id + '_fill_pattern.gds')
+        print('This script will generate files ' + project_with_id + '_fill_pattern_x_y.gds')
+        print('Now generating fill patterns.  This may take. . . quite. . . a while.', flush=True)
+        mproc = subprocess.run(['magic', '-dnull', '-noconsole',
+		'-rcfile', rcfile, magpath + '/generate_fill.tcl'],
+		stdin = subprocess.DEVNULL,
+		stdout = subprocess.PIPE,
+		stderr = subprocess.PIPE,
+		cwd = magpath,
+		env = myenv,
+		universal_newlines = True)
+        if mproc.stdout:
+            for line in mproc.stdout.splitlines():
+                print(line)
+        if mproc.stderr:
+            print('Error message output from magic:')
+            for line in mproc.stderr.splitlines():
+                print(line)
+            if mproc.returncode != 0:
+                print('ERROR:  Magic exited with status ' + str(mproc.returncode))
+
+        if distmode:
+            # If using distributed mode, then run magic on each of the generated
+            # layout files
+            pool = multiprocessing.Pool()
+            magfiles = glob.glob(magpath + '/' + project_with_id + '_fill_pattern_*.mag')
+            # NOTE:  Adding 'x' to the end of each filename, or else magic will
+            # try to read it from the command line as well as passing it as an
+            # argument to the script.  We only want it passed as an argument.
+            magxfiles = list(item + 'x' for item in magfiles)
+            pool.map(makegds, magxfiles)
+
+            # If using distributed mode, then remove all of the temporary .mag files
+            # and then run the final generation script.
+            for file in magfiles:
+                os.remove(file)
+
+            mproc = subprocess.run(['magic', '-dnull', '-noconsole',
+			'-rcfile', rcfile, magpath + '/generate_fill_final.tcl'],
+			stdin = subprocess.DEVNULL,
+			stdout = subprocess.PIPE,
+			stderr = subprocess.PIPE,
+			cwd = magpath,
+			env = myenv,
+			universal_newlines = True)
+            if mproc.stdout:
+                for line in mproc.stdout.splitlines():
+                    print(line)
+            if mproc.stderr:
+                print('Error message output from magic:')
+                for line in mproc.stderr.splitlines():
+                    print(line)
+                if mproc.returncode != 0:
+                    print('ERROR:  Magic exited with status ' + str(mproc.returncode))
+
+    if not keepmode:
+        # Remove fill generation script
+        os.remove(magpath + '/generate_fill.tcl')
+        # Remove all individual fill tiles, leaving only the composite GDS.
+        filelist = os.listdir(magpath)
+        for file in filelist:
+            if os.path.splitext(magpath + '/' + file)[1] == '.gds':
+                if file.startswith(project_with_id + '_fill_pattern_'):
+                    os.remove(magpath + '/' + file)
+
+        if distmode:
+            os.remove(magpath + '/generate_fill_dist.tcl')
+            os.remove(magpath + '/generate_fill_final.tcl')
+            os.remove(magpath + '/fill_gen_info.txt')
+            if testmode:
+                magfiles = glob.glob(magpath + '/' + project_with_id + '_fill_pattern_*.mag')
+                for file in magfiles:
+                    os.remove(file)
+
+    print('Done!')
+    exit(0)
diff --git a/caravel/scripts/generate_fill_orig.py b/caravel/scripts/generate_fill_orig.py
new file mode 100644
index 0000000..3a43a8c
--- /dev/null
+++ b/caravel/scripts/generate_fill_orig.py
@@ -0,0 +1,268 @@
+#!/usr/bin/env python3
+# SPDX-FileCopyrightText: 2020 Efabless Corporation
+#
+# Licensed under the Apache License, Version 2.0 (the "License");
+# you may not use this file except in compliance with the License.
+# You may obtain a copy of the License at
+#
+#      http://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing, software
+# distributed under the License is distributed on an "AS IS" BASIS,
+# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+# See the License for the specific language governing permissions and
+# limitations under the License.
+# SPDX-License-Identifier: Apache-2.0
+
+#
+# generate_fill_orig.py ---
+#
+#    Run the fill generation on a layout top level.
+#    This is the older version that does not have a "-dist" option for
+#    distributed (multiprocessing) operation.
+#
+
+import sys
+import os
+import re
+import subprocess
+
+def usage():
+    print("Usage:")
+    print("generate_fill_orig.py [<path_to_project>] [-keep] [-test]")
+    print("")
+    print("where:")
+    print("    <path_to_project> is the path to the project top level directory.")
+    print("")
+    print("  If <path_to_project> is not given, then it is assumed to be the cwd.")
+    print("  If '-keep' is specified, then keep the generation script.")
+    print("  If '-test' is specified, then create but do not run the generation script.")
+    return 0
+
+if __name__ == '__main__':
+
+    optionlist = []
+    arguments = []
+
+    debugmode = False
+    keepmode = False
+    testmode = False
+
+    for option in sys.argv[1:]:
+        if option.find('-', 0) == 0:
+            optionlist.append(option)
+        else:
+            arguments.append(option)
+
+    if len(arguments) > 1:
+        print("Wrong number of arguments given to generate_fill_orig.py.")
+        usage()
+        sys.exit(1)
+
+    if len(arguments) == 1:
+        user_project_path = arguments[0]
+    else:
+        user_project_path = os.getcwd()
+
+    if not os.path.isdir(user_project_path):
+        print('Error:  Project path "' + user_project_path + '" does not exist or is not readable.')
+        sys.exit(1)
+
+    # Check for valid user ID
+    user_id_value = None
+    if os.path.isfile(user_project_path + '/info.yaml'):
+        with open(user_project_path + '/info.yaml', 'r') as ifile:
+            infolines = ifile.read().splitlines()
+            for line in infolines:
+                kvpair = line.split(':')
+                if len(kvpair) == 2:
+                    key = kvpair[0].strip()
+                    value = kvpair[1].strip()
+                    if key == 'project_id':
+                        user_id_value = value.strip('"\'')
+                        break
+
+    project = 'caravel'
+    if user_id_value:
+        project_with_id = project + '_' + user_id_value
+    else:
+        print('Error:  No project_id found in info.yaml file.')
+        sys.exit(1)
+
+    if '-debug' in optionlist:
+        debugmode = True
+    if '-keep' in optionlist:
+        keepmode = True
+    if '-test' in optionlist:
+        testmode = True
+
+    magpath = user_project_path + '/mag'
+    rcfile = magpath + '/.magicrc'
+
+    if not os.path.isfile(rcfile):
+        rcfile = None
+
+    topdir = user_project_path
+    gdsdir = topdir + '/gds'
+    hasgdsdir = True if os.path.isdir(gdsdir) else False
+
+    with open(magpath + '/generate_fill.tcl', 'w') as ofile:
+        print('#!/bin/env wish', file=ofile)
+        print('drc off', file=ofile)
+        print('tech unlock *', file=ofile)
+        print('snap internal', file=ofile)
+        print('box values 0 0 0 0', file=ofile)
+        print('box size 700um 700um', file=ofile)
+        print('set stepbox [box values]', file=ofile)
+        print('set stepwidth [lindex $stepbox 2]', file=ofile)
+        print('set stepheight [lindex $stepbox 3]', file=ofile)
+        print('', file=ofile)
+        print('set starttime [orig_clock format [orig_clock seconds] -format "%D %T"]', file=ofile)
+        print('puts stdout "Started: $starttime"', file=ofile)
+        print('', file=ofile)
+        # Read the user project from GDS, as there is not necessarily a magic database file
+        # to go along with this.
+        # print('gds read ../gds/user_project_wrapper', file=ofile)
+        # Now read the full caravel project
+        # print('load ' + project + ' -dereference', file=ofile)
+        print('gds readonly true', file=ofile)
+        print('gds rescale false', file=ofile)
+        print('gds read ../gds/caravel', file=ofile)
+        print('select top cell', file=ofile)
+        print('expand', file=ofile)
+        print('cif ostyle wafflefill(tiled)', file=ofile)
+        print('', file=ofile)
+        print('set fullbox [box values]', file=ofile)
+        print('set xmax [lindex $fullbox 2]', file=ofile)
+        print('set xmin [lindex $fullbox 0]', file=ofile)
+        print('set fullwidth [expr {$xmax - $xmin}]', file=ofile)
+        print('set xtiles [expr {int(ceil(($fullwidth + 0.0) / $stepwidth))}]', file=ofile)
+        print('set ymax [lindex $fullbox 3]', file=ofile)
+        print('set ymin [lindex $fullbox 1]', file=ofile)
+        print('set fullheight [expr {$ymax - $ymin}]', file=ofile)
+        print('set ytiles [expr {int(ceil(($fullheight + 0.0) / $stepheight))}]', file=ofile)
+        print('box size $stepwidth $stepheight', file=ofile)
+        print('set xbase [lindex $fullbox 0]', file=ofile)
+        print('set ybase [lindex $fullbox 1]', file=ofile)
+        print('', file=ofile)
+
+        # Break layout into tiles and process each separately
+        print('for {set y 0} {$y < $ytiles} {incr y} {', file=ofile)
+        print('    for {set x 0} {$x < $xtiles} {incr x} {', file=ofile)
+        print('        set xlo [expr $xbase + $x * $stepwidth]', file=ofile)
+        print('        set ylo [expr $ybase + $y * $stepheight]', file=ofile)
+        print('        set xhi [expr $xlo + $stepwidth]', file=ofile)
+        print('        set yhi [expr $ylo + $stepheight]', file=ofile)
+        print('        if {$xhi > $fullwidth} {set xhi $fullwidth}', file=ofile)
+        print('        if {$yhi > $fullheight} {set yhi $fullheight}', file=ofile)
+        print('        box values $xlo $ylo $xhi $yhi', file=ofile)
+        # The flattened area must be larger than the fill tile by >1.5um
+        print('        box grow c 1.6um', file=ofile)
+
+        # Flatten into a cell with a new name
+        print('        puts stdout "Flattening layout of tile x=$x y=$y. . . "', file=ofile)
+        print('        flush stdout', file=ofile)
+        print('        update idletasks', file=ofile)
+        print('        flatten -dobox -nolabels ' + project_with_id + '_fill_pattern_${x}_$y', file=ofile)
+        print('        load ' + project_with_id + '_fill_pattern_${x}_$y', file=ofile)
+
+        # Remove any GDS_FILE reference (there should not be any?)
+        print('        property GDS_FILE ""', file=ofile)
+        # Set boundary using comment layer, to the size of the step box
+	# This corresponds to the "topbox" rule in the wafflefill(tiled) style
+        print('        select top cell', file=ofile)
+        print('        erase comment', file=ofile)
+        print('        box values $xlo $ylo $xhi $yhi', file=ofile)
+        print('        paint comment', file=ofile)
+        print('        puts stdout "Writing GDS. . . "', file=ofile)
+        print('        flush stdout', file=ofile)
+        print('        update idletasks', file=ofile)
+        print('        gds write ' + project_with_id + '_fill_pattern_${x}_$y.gds', file=ofile)
+
+        # Reload project top
+        print('        load ' + project, file=ofile)
+
+        # Remove last generated cell to save memory
+        print('        cellname delete ' + project_with_id + '_fill_pattern_${x}_$y', file=ofile)
+
+        print('    }', file=ofile)
+        print('}', file=ofile)
+
+        # Now create simple "fake" views of all the tiles.
+        print('gds readonly true', file=ofile)
+        print('gds rescale false', file=ofile)
+        print('for {set y 0} {$y < $ytiles} {incr y} {', file=ofile)
+        print('    for {set x 0} {$x < $xtiles} {incr x} {', file=ofile)
+        print('        set xlo [expr $xbase + $x * $stepwidth]', file=ofile)
+        print('        set ylo [expr $ybase + $y * $stepheight]', file=ofile)
+        print('        set xhi [expr $xlo + $stepwidth]', file=ofile)
+        print('        set yhi [expr $ylo + $stepheight]', file=ofile)
+        print('        load ' + project_with_id + '_fill_pattern_${x}_$y -quiet', file=ofile)
+        print('        box values $xlo $ylo $xhi $yhi', file=ofile)
+        print('        paint comment', file=ofile)
+        print('        property FIXED_BBOX "$xlo $ylo $xhi $yhi"', file=ofile)
+        print('        property GDS_FILE ' + project_with_id + '_fill_pattern_${x}_${y}.gds', file=ofile)
+        print('        property GDS_START 0', file=ofile)
+        print('    }', file=ofile)
+        print('}', file=ofile)
+
+        # Now tile everything back together
+        print('load ' + project_with_id + '_fill_pattern -quiet', file=ofile)
+        print('for {set y 0} {$y < $ytiles} {incr y} {', file=ofile)
+        print('    for {set x 0} {$x < $xtiles} {incr x} {', file=ofile)
+        print('        box values 0 0 0 0', file=ofile)
+        print('        getcell ' + project_with_id + '_fill_pattern_${x}_$y child 0 0', file=ofile)
+        print('    }', file=ofile)
+        print('}', file=ofile)
+
+        # And write final GDS
+        print('puts stdout "Writing final GDS"', file=ofile)
+
+        print('cif *hier write disable', file=ofile)
+        print('cif *array write disable', file=ofile)
+        if hasgdsdir:
+            print('gds write ../gds/' + project_with_id + '_fill_pattern.gds', file=ofile)
+        else:
+            print('gds write ' + project_with_id + '_fill_pattern.gds', file=ofile)
+        print('set endtime [orig_clock format [orig_clock seconds] -format "%D %T"]', file=ofile)
+        print('puts stdout "Ended: $endtime"', file=ofile)
+        print('quit -noprompt', file=ofile)
+
+    myenv = os.environ.copy()
+    myenv['MAGTYPE'] = 'mag'
+
+    if not testmode:
+        # Diagnostic
+        # print('This script will generate file ' + project_with_id + '_fill_pattern.gds')
+        print('This script will generate files ' + project_with_id + '_fill_pattern_x_y.gds')
+        print('Now generating fill patterns.  This may take. . . quite. . . a while.', flush=True)
+        mproc = subprocess.run(['magic', '-dnull', '-noconsole',
+		'-rcfile', rcfile, magpath + '/generate_fill.tcl'],
+		stdin = subprocess.DEVNULL,
+		stdout = subprocess.PIPE,
+		stderr = subprocess.PIPE,
+		cwd = magpath,
+		env = myenv,
+		universal_newlines = True)
+        if mproc.stdout:
+            for line in mproc.stdout.splitlines():
+                print(line)
+        if mproc.stderr:
+            print('Error message output from magic:')
+            for line in mproc.stderr.splitlines():
+                print(line)
+            if mproc.returncode != 0:
+                print('ERROR:  Magic exited with status ' + str(mproc.returncode))
+
+    if not keepmode:
+        # Remove fill generation script
+        os.remove(magpath + '/generate_fill.tcl')
+        # Remove all individual fill tiles, leaving only the composite GDS.
+        filelist = os.listdir(magpath)
+        for file in filelist:
+            if os.path.splitext(magpath + '/' + file)[1] == '.gds':
+                if file.startswith(project + '_fill_pattern_'):
+                    os.remove(magpath + '/' + file)
+
+    print('Done!')
+    exit(0)
diff --git a/caravel/scripts/make_bump_bonds.tcl b/caravel/scripts/make_bump_bonds.tcl
new file mode 100644
index 0000000..ade81d6
--- /dev/null
+++ b/caravel/scripts/make_bump_bonds.tcl
@@ -0,0 +1,702 @@
+# SPDX-FileCopyrightText: 2020 Efabless Corporation
+#
+# Licensed under the Apache License, Version 2.0 (the "License");
+# you may not use this file except in compliance with the License.
+# You may obtain a copy of the License at
+#
+#      http://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing, software
+# distributed under the License is distributed on an "AS IS" BASIS,
+# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+# See the License for the specific language governing permissions and
+# limitations under the License.
+# SPDX-License-Identifier: Apache-2.0
+#----------------------------------------------------------------------
+# Assumes running magic -T micross using the micross technology file
+# from the open_pdks installation of sky130A
+#----------------------------------------------------------------------
+# bump bond pitch is 500um.  Bump diameter is set by the technology
+
+namespace path {::tcl::mathop ::tcl::mathfunc}
+
+if {[catch {set PDKPATH $env(PDKPATH)}]} {
+    set PDKPATH "$::env(PDK_ROOT)/sky130A"
+}
+
+source $PDKPATH/libs.tech/magic/current/bump_bond_generator/bump_bond.tcl
+
+# Caravel dimensions, in microns
+set chipwidth 3588
+set chipheight 5188
+
+set halfwidth [/ $chipwidth 2]
+set halfheight [/ $chipheight 2]
+
+set columns 6
+set rows 10
+
+set bump_pitch 500
+
+set llx [- $halfwidth [* [- [/ $columns 2] 0.5] $bump_pitch]]
+set lly [- $halfheight [* [- [/ $rows 2] 0.5] $bump_pitch]]
+
+# Create a new cell
+load caravel_bump_bond -quiet
+
+# Build the bump cells
+make_bump_bond 0
+make_bump_bond 45
+
+# View the whole chip during generation.  This is not strictly
+# necessary, but looks nice!
+snap internal
+box values 0 0 ${chipwidth}um ${chipheight}um
+paint glass
+view
+erase glass
+box values 0 0 0 0
+grid 250um 250um 45um 95um
+
+# Starting from the bottom left-hand corner and scanning across and up,
+# these are the orientations of the bump bond pad tapers:
+set tapers {}
+lappend tapers 180 225 270 270 270 270
+lappend tapers 180 135 225 270   0   0
+lappend tapers 180 135 135 270 315   0
+lappend tapers 180 135 135 315 315   0
+lappend tapers 135 135   0 180 315   0
+lappend tapers 180 135   0 180 315   0
+lappend tapers 180 135 180 315 315   0
+lappend tapers 180 180 135  45 315   0
+lappend tapers 135 135 135  45  45  45
+lappend tapers  90  90  90  90  45  90
+
+box values 0 0 0 0
+set t 0
+for {set y 0} {$y < $rows} {incr y} {
+    for {set x 0} {$x < $columns} {incr x} {
+        set xpos [+ $llx [* $x $bump_pitch]]
+        set ypos [+ $lly [* $y $bump_pitch]]
+	draw_bump_bond $xpos $ypos [lindex $tapers $t]
+	incr t
+    }
+}
+
+# The pad at E6 has wires exiting two sides, so put another pad down
+# at the other orientation.
+set y 4
+set x 4
+set xpos [+ $llx [* $x $bump_pitch]]
+set ypos [+ $lly [* $y $bump_pitch]]
+draw_bump_bond $xpos $ypos 180
+
+select top cell
+expand
+
+# These are the pad Y positions on the left side from bottom to top
+
+set leftpads {}
+lappend leftpads 377.5 588.5 950.5 1166.5 1382.5 1598.5 1814.5
+lappend leftpads 2030.5 2241.5 2452.5 2668.5 2884.5 3100.5
+lappend leftpads 3316.5 3532.5 3748.5 3964.5 4175.5 4386.5 4597.5 4813.5
+
+# These are the pad X positions on the top side from left to right
+
+set toppads {}
+lappend toppads 423.5 680.5 937.5 1194.5 1452.5 1704.5 1961.5 2406.5
+lappend toppads 2663.5 2915.5 3172.5
+
+# These are the pad Y positions on the right side from bottom to top
+
+set rightpads {}
+lappend rightpads 537.5 763.5 988.5 1214.5 1439.5 1664.5 1890.5
+lappend rightpads 2115.5 2336.5 2556.5 2776.5 3002.5 3227.5 3453.5
+lappend rightpads 3678.5 3903.5 4129.5 4349.5 4575.5 4795.5
+
+# These are the pad X positions on the bottom side from left to right
+
+set bottompads {}
+lappend bottompads 431.5 700.5 969.5 1243.5 1512.5 1786.5 2060.5
+lappend bottompads 2334.5 2608.5 2882.5 3151.5
+
+set leftpadx 64.6
+set rightpadx 3523.78
+set bottompady 64.6
+set toppady 5123.78
+
+set xpos $leftpadx
+for {set y 0} {$y < [llength $leftpads]} {incr y} {
+    set ypos [lindex $leftpads $y]
+    draw_pad_bond $xpos $ypos
+}
+
+set ypos $toppady
+for {set x 0} {$x < [llength $toppads]} {incr x} {
+    set xpos [lindex $toppads $x]
+    draw_pad_bond $xpos $ypos
+}
+
+set xpos $rightpadx
+for {set y 0} {$y < [llength $rightpads]} {incr y} {
+    set ypos [lindex $rightpads $y]
+    draw_pad_bond $xpos $ypos
+}
+
+set ypos $bottompady
+for {set x 0} {$x < [llength $bottompads]} {incr x} {
+    set xpos [lindex $bottompads $x]
+    draw_pad_bond $xpos $ypos
+}
+
+# Now route between the wirebond pads and the bump bond pads
+# routes start centered on the wirebond pad and align to grid points
+# on a 1/2 ball pitch, although positions do not need to be on
+# integer values.  The overlaid grid starts 1/2 pitch to the left
+# and below the center of the bottom left bump bond.  Grid columns
+# are numbered 0 to 12, and grid rows are numbered 0 to 20.  To
+# convert to a micron unit coordinate, use the to_grid procedure
+# defined below.
+
+set gridllx [- $llx 250.0]
+set gridlly [- $lly 250.0]
+set gridpitchx 250.0
+set gridpitchy 250.0
+
+proc to_grid {x y} {
+    global gridllx gridlly
+    set coords []
+    catch {lappend coords [+ $gridllx [* 250.0 $x]]}
+    catch {lappend coords [+ $gridlly [* 250.0 $y]]}
+    return $coords
+}
+
+# Detailed routing, scanning left to right and from bottom to top.
+# (This really needs to be automated. . .)
+
+set wire_width 40.0
+
+# A10 vccd
+set coords [list $leftpadx [lindex $leftpads 0]]
+lappend coords {*}[to_grid -0.8 1]
+lappend coords {*}[to_grid 1 1]
+draw_pad_route $coords $wire_width
+
+# B10 resetb
+set coords [list [lindex $bottompads 1] $bottompady]
+lappend coords {*}[to_grid 1.9 0.2]
+lappend coords {*}[to_grid 2.2 0.2]
+lappend coords {*}[to_grid 3 1]
+draw_pad_route $coords $wire_width
+
+# C10 flash csb
+set coords [list [lindex $bottompads 4] $bottompady]
+lappend coords {*}[to_grid 5 0]
+lappend coords {*}[to_grid 5 1]
+draw_pad_route $coords $wire_width
+
+# D10 flash io0
+set coords [list [lindex $bottompads 6] $bottompady]
+lappend coords {*}[to_grid 7 0]
+lappend coords {*}[to_grid 7 1]
+draw_pad_route $coords $wire_width
+
+# E10 gpio
+set coords [list [lindex $bottompads 8] $bottompady]
+lappend coords {*}[to_grid 9 0.2]
+lappend coords {*}[to_grid 9 1]
+draw_pad_route $coords $wire_width
+
+# F10 vdda
+set coords [list [lindex $bottompads 10] $bottompady]
+lappend coords {*}[to_grid 11 0.3]
+lappend coords {*}[to_grid 11 1]
+draw_pad_route $coords $wire_width
+
+# A9 mprj_io[37]
+set coords [list $leftpadx [lindex $leftpads 2]]
+lappend coords {*}[to_grid -0.5 3]
+lappend coords {*}[to_grid 1 3]
+draw_pad_route $coords $wire_width
+
+# B9 mprj_io[36]
+set coords [list $leftpadx [lindex $leftpads 3]]
+lappend coords {*}[to_grid -0.6 4]
+lappend coords {*}[to_grid 2 4]
+lappend coords {*}[to_grid 3 3]
+draw_pad_route $coords $wire_width
+
+# C9 clock
+set coords [list [lindex $bottompads 2] $bottompady]
+lappend coords {*}[to_grid 3 0.2]
+lappend coords {*}[to_grid 3.4 0.2]
+lappend coords {*}[to_grid 3.8 0.6]
+lappend coords {*}[to_grid 3.8 1.6]
+lappend coords {*}[to_grid 4.5 2.3]
+lappend coords {*}[to_grid 4.5 2.5]
+lappend coords {*}[to_grid 5 3]
+draw_pad_route $coords $wire_width
+
+# D9 flash io1
+set coords [list [lindex $bottompads 7] $bottompady]
+lappend coords {*}[to_grid 8 0.1]
+lappend coords {*}[to_grid 8 1.3]
+lappend coords {*}[to_grid 7 2.3]
+lappend coords {*}[to_grid 7 3]
+draw_pad_route $coords $wire_width
+
+# E9 mprj_io[1]/SDO
+set coords [list $rightpadx [lindex $rightpads 1]]
+lappend coords {*}[to_grid 12.4 2.2]
+lappend coords {*}[to_grid 10.5 2.2]
+lappend coords {*}[to_grid 9.7 3]
+lappend coords {*}[to_grid 9 3]
+draw_pad_route $coords $wire_width
+
+# F9 mprj_io[2]/SDI
+set coords [list $rightpadx [lindex $rightpads 2]]
+lappend coords {*}[to_grid 12.3 3]
+lappend coords {*}[to_grid 11 3]
+draw_pad_route $coords $wire_width
+
+# A8 mprj_io[35]
+set coords [list $leftpadx [lindex $leftpads 4]]
+lappend coords {*}[to_grid -0.7 5]
+lappend coords {*}[to_grid 1 5]
+draw_pad_route $coords $wire_width
+
+# B8 mprj_io[34]
+set coords [list $leftpadx [lindex $leftpads 5]]
+lappend coords {*}[to_grid -0.7 5.8]
+lappend coords {*}[to_grid 2.2 5.8]
+lappend coords {*}[to_grid 3 5]
+draw_pad_route $coords $wire_width
+
+# C8 mprj_io[33]
+set coords [list $leftpadx [lindex $leftpads 6]]
+lappend coords {*}[to_grid -0.3 6.2]
+lappend coords {*}[to_grid 3.8 6.2]
+lappend coords {*}[to_grid 5 5]
+draw_pad_route $coords $wire_width
+
+# D8 flash clk
+set coords [list [lindex $bottompads 5] $bottompady]
+lappend coords {*}[to_grid 6 0]
+lappend coords {*}[to_grid 6 1]
+lappend coords {*}[to_grid 6.2 1.2]
+lappend coords {*}[to_grid 6.2 3.5]
+lappend coords {*}[to_grid 7 4.3]
+lappend coords {*}[to_grid 7 5]
+draw_pad_route $coords $wire_width
+
+# E8 mprj_io[3]/CSB
+set coords [list $rightpadx [lindex $rightpads 3]]
+lappend coords {*}[to_grid 12.4 4]
+lappend coords {*}[to_grid 10 4]
+lappend coords {*}[to_grid 9 5]
+draw_pad_route $coords $wire_width
+
+# F8 mrpj_io[4]/SCK
+set coords [list $rightpadx [lindex $rightpads 4]]
+lappend coords {*}[to_grid 12.5 5]
+lappend coords {*}[to_grid 11 5]
+draw_pad_route $coords $wire_width
+
+# A7 mrpj_io[32]
+set coords [list $leftpadx [lindex $leftpads 7]]
+lappend coords {*}[to_grid -0.2 7]
+lappend coords {*}[to_grid 1 7]
+draw_pad_route $coords $wire_width
+
+# B7 vssd2
+set coords [list $leftpadx [lindex $leftpads 8]]
+lappend coords {*}[to_grid -0.1 7.8]
+lappend coords {*}[to_grid 2.2 7.8]
+lappend coords {*}[to_grid 3 7]
+draw_pad_route $coords $wire_width
+
+# C7 vdda2
+set coords [list $leftpadx [lindex $leftpads 9]]
+lappend coords {*}[to_grid 0.3 8.2]
+lappend coords {*}[to_grid 2.3 8.2]
+lappend coords {*}[to_grid 2.5 8]
+lappend coords {*}[to_grid 4 8]
+lappend coords {*}[to_grid 5 7]
+draw_pad_route $coords $wire_width
+
+# D7 mrpj_io[0]/JTAG
+set coords [list $rightpadx [lindex $rightpads 0]]
+lappend coords {*}[to_grid 12.8 1.8]
+lappend coords {*}[to_grid 10.2 1.8]
+lappend coords {*}[to_grid 9.8 2.2]
+lappend coords {*}[to_grid 8.6 2.2]
+lappend coords {*}[to_grid 8.2 2.6]
+lappend coords {*}[to_grid 8.2 5.8]
+lappend coords {*}[to_grid 7 7]
+draw_pad_route $coords $wire_width
+
+# E7 mrpj_io[5]/ser_rx
+set coords [list $rightpadx [lindex $rightpads 5]]
+lappend coords {*}[to_grid 12.6 6]
+lappend coords {*}[to_grid 10 6]
+lappend coords {*}[to_grid 9 7]
+draw_pad_route $coords $wire_width
+
+# F7 mprj_io[6]/ser_tx
+set coords [list $rightpadx [lindex $rightpads 6]]
+lappend coords {*}[to_grid 12.7 7]
+lappend coords {*}[to_grid 11 7]
+draw_pad_route $coords $wire_width
+
+# A6 mprj_io[31]
+set coords [list $leftpadx [lindex $leftpads 10]]
+lappend coords {*}[to_grid -0.3 10.3]
+lappend coords {*}[to_grid 1 9]
+draw_pad_route $coords $wire_width
+
+# B6 mprj_io[30]
+set coords [list $leftpadx [lindex $leftpads 11]]
+lappend coords {*}[to_grid -0.5 10.8]
+lappend coords {*}[to_grid -0.3 10.8]
+lappend coords {*}[to_grid 0.5 10]
+lappend coords {*}[to_grid 2 10]
+lappend coords {*}[to_grid 3 9]
+draw_pad_route $coords $wire_width
+
+# C6 vssio/vssa/vssd:  Connects to D6, D5, C5
+set coords [to_grid 5 9]
+lappend coords {*}[to_grid 5.65 9]
+lappend coords {*}[to_grid 5.85 9.2]
+lappend coords {*}[to_grid 6 9.2]
+draw_pad_route $coords $wire_width
+
+# D6 vssio/vssa/vssd
+set coords [to_grid 7 9]
+lappend coords {*}[to_grid 6.35 9]
+lappend coords {*}[to_grid 6.15 8.8]
+lappend coords {*}[to_grid 6 8.8]
+draw_pad_route $coords $wire_width
+
+# D6 vssio/vssa/vssd also goes to:
+set coords [list [lindex $bottompads 0] $bottompady]
+lappend coords {*}[to_grid 0.9 0.2]
+lappend coords {*}[to_grid 1.3 0.2]
+lappend coords {*}[to_grid 2 0.9]
+lappend coords {*}[to_grid 2 1.5]
+lappend coords {*}[to_grid 2.3 1.8]
+lappend coords {*}[to_grid 3.5 1.8]
+lappend coords {*}[to_grid 4.2 2.5]
+lappend coords {*}[to_grid 4.2 3.5]
+lappend coords {*}[to_grid 4.5 3.8]
+lappend coords {*}[to_grid 5.3 3.8]
+lappend coords {*}[to_grid 5.8 3.3]
+lappend coords {*}[to_grid 5.8 2.5]
+lappend coords {*}[to_grid 5.3 2]
+lappend coords {*}[to_grid 4.8 2]
+lappend coords {*}[to_grid 4.2 1.4]
+lappend coords {*}[to_grid 4.2 0.3]
+lappend coords {*}[list [lindex $bottompads 3] $bottompady]
+draw_pad_route $coords $wire_width
+
+# D6 vssio/vssa/vssd also goes to:
+set coords [list [lindex $bottompads 9] $bottompady]
+lappend coords {*}[to_grid 10 0.3]
+lappend coords {*}[to_grid 10 1.4]
+lappend coords {*}[to_grid 9.6 1.8]
+lappend coords {*}[to_grid 8.5 1.8]
+lappend coords {*}[to_grid 7.8 2.5]
+lappend coords {*}[to_grid 7.8 5.5]
+lappend coords {*}[to_grid 7.3 6]
+lappend coords {*}[to_grid 6.2 6]
+draw_pad_route $coords $wire_width
+
+# D6 vssio/vssa/vssd also goes to:
+set coords [list [lindex $toppads 5] $toppady]
+lappend coords {*}[to_grid 6 19.7]
+lappend coords {*}[to_grid 6 16]
+lappend coords {*}[to_grid 5.8 15.8]
+lappend coords {*}[to_grid 5.8 12.2]
+lappend coords {*}[to_grid 6 12]
+lappend coords {*}[to_grid 6 8]
+lappend coords {*}[to_grid 6.2 7.8]
+lappend coords {*}[to_grid 6.2 4.3]
+lappend coords {*}[to_grid 5.5 3.6]
+draw_pad_route $coords $wire_width
+
+# E6 vssa1
+set coords [list $rightpadx [lindex $rightpads 7]]
+lappend coords {*}[to_grid 12.8 8]
+lappend coords {*}[to_grid 10 8]
+lappend coords {*}[to_grid 9 9]
+draw_pad_route $coords $wire_width
+
+# E6 vssa1 also goes to
+set coords [list [lindex $toppads 9] $toppady]
+lappend coords {*}[to_grid 10 19.5]
+lappend coords {*}[to_grid 10 18.5]
+lappend coords {*}[to_grid 9.5 18]
+lappend coords {*}[to_grid 8.5 18]
+lappend coords {*}[to_grid 8 17.5]
+lappend coords {*}[to_grid 8 16.5]
+lappend coords {*}[to_grid 7.5 16]
+lappend coords {*}[to_grid 6.7 16]
+lappend coords {*}[to_grid 6.2 15.5]
+lappend coords {*}[to_grid 6.2 12.6]
+lappend coords {*}[to_grid 6.7 12]
+lappend coords {*}[to_grid 7.3 12]
+lappend coords {*}[to_grid 7.8 11.5]
+lappend coords {*}[to_grid 7.8 10.2]
+lappend coords {*}[to_grid 8 10]
+lappend coords {*}[to_grid 8 9.3]
+lappend coords {*}[to_grid 8.3 9]
+lappend coords {*}[to_grid 9 9]
+draw_pad_route $coords $wire_width
+
+# F6 vssd1
+set coords [list $rightpadx [lindex $rightpads 8]]
+lappend coords {*}[to_grid 12.9 9]
+lappend coords {*}[to_grid 11 9]
+draw_pad_route $coords $wire_width
+
+# A5 mprj_io[29]
+set coords [list $leftpadx [lindex $leftpads 12]]
+lappend coords {*}[to_grid 0.2 11]
+lappend coords {*}[to_grid 1 11]
+draw_pad_route $coords $wire_width
+
+# B5 mprj_io[28]
+set coords [list $leftpadx [lindex $leftpads 13]]
+lappend coords {*}[to_grid 0 12]
+lappend coords {*}[to_grid 2 12]
+lappend coords {*}[to_grid 3 11]
+draw_pad_route $coords $wire_width
+
+# C5 vssio/vssa/vssd :  Connects to D6, C6, D5
+set coords [to_grid 5 11]
+lappend coords {*}[to_grid 5.65 11]
+lappend coords {*}[to_grid 5.85 11.2]
+lappend coords {*}[to_grid 6 11.2]
+draw_pad_route $coords $wire_width
+
+# D5 vssio/vssa/vssd :  Connects to D6, C6, C5
+set coords [to_grid 7 11]
+lappend coords {*}[to_grid 6.35 11]
+lappend coords {*}[to_grid 6.15 10.8]
+lappend coords {*}[to_grid 6 10.8]
+draw_pad_route $coords $wire_width
+
+# E5 mprj_io[7]/irq
+set coords [list $rightpadx [lindex $rightpads 10]]
+lappend coords {*}[to_grid 12.4 10.2]
+lappend coords {*}[to_grid 9.8 10.2]
+lappend coords {*}[to_grid 9 11]
+draw_pad_route $coords $wire_width
+
+# F5 mprj_io[8]/flash2 csb
+set coords [list $rightpadx [lindex $rightpads 11]]
+lappend coords {*}[to_grid 12.3 11]
+lappend coords {*}[to_grid 11 11]
+draw_pad_route $coords $wire_width
+
+# A4 mprj_io[27]
+set coords [list $leftpadx [lindex $leftpads 14]]
+lappend coords {*}[to_grid -0.1 13]
+lappend coords {*}[to_grid 1 13]
+draw_pad_route $coords $wire_width
+
+# B4 mprj_io[26]
+set coords [list $leftpadx [lindex $leftpads 15]]
+lappend coords {*}[to_grid -0.2 14]
+lappend coords {*}[to_grid 2 14]
+lappend coords {*}[to_grid 3 13]
+draw_pad_route $coords $wire_width
+
+# C4 vddio
+set coords [list $leftpadx [lindex $leftpads 1]]
+lappend coords {*}[to_grid -0.8 2]
+lappend coords {*}[to_grid 1.8 2]
+lappend coords {*}[to_grid 2 2.2]
+lappend coords {*}[to_grid 3.3 2.2]
+lappend coords {*}[to_grid 3.8 2.7]
+lappend coords {*}[to_grid 3.8 3.7]
+lappend coords {*}[to_grid 4.3 4.2]
+lappend coords {*}[to_grid 5.3 4.2]
+lappend coords {*}[to_grid 5.8 4.7]
+lappend coords {*}[to_grid 5.8 7.4]
+lappend coords {*}[to_grid 5.2 8]
+lappend coords {*}[to_grid 4.7 8]
+lappend coords {*}[to_grid 4 8.7]
+lappend coords {*}[to_grid 4 13]
+draw_pad_route $coords $wire_width
+
+# C4 vddio is also:
+set coords [list $leftpadx [lindex $leftpads 18]]
+lappend coords {*}[to_grid 0.1 16.2]
+lappend coords {*}[to_grid 1.6 16.2]
+lappend coords {*}[to_grid 2 15.8]
+lappend coords {*}[to_grid 3.4 15.8]
+lappend coords {*}[to_grid 4 15.2]
+lappend coords {*}[to_grid 4 13]
+lappend coords {*}[to_grid 5 13]
+draw_pad_route $coords $wire_width
+
+# D4 vdda1
+set coords [list $rightpadx [lindex $rightpads 9]]
+lappend coords {*}[to_grid 12.8 9.8]
+lappend coords {*}[to_grid 9.7 9.8]
+lappend coords {*}[to_grid 9.5 10]
+lappend coords {*}[to_grid 8.8 10]
+lappend coords {*}[to_grid 8.2 10.6]
+lappend coords {*}[to_grid 8.2 11.8]
+lappend coords {*}[to_grid 7 13]
+draw_pad_route $coords $wire_width
+
+# D4 vdda1 is also:
+set coords [list $rightpadx [lindex $rightpads 16]]
+lappend coords {*}[to_grid 12.6 15.8]
+lappend coords {*}[to_grid 8.4 15.8]
+lappend coords {*}[to_grid 8 15.4]
+lappend coords {*}[to_grid 8 12.4]
+lappend coords {*}[to_grid 7.8 12.2]
+draw_pad_route $coords $wire_width
+
+# E4 mprj_io[9]/flash2 sck
+set coords [list $rightpadx [lindex $rightpads 12]]
+lappend coords {*}[to_grid 12.4 12]
+lappend coords {*}[to_grid 10 12]
+lappend coords {*}[to_grid 9 13]
+draw_pad_route $coords $wire_width
+
+# F4 mprj_io[10]/flash2 io0
+set coords [list $rightpadx [lindex $rightpads 13]]
+lappend coords {*}[to_grid 12.5 13]
+lappend coords {*}[to_grid 11 13]
+draw_pad_route $coords $wire_width
+
+# A3 mprj_io[25]
+set coords [list $leftpadx [lindex $leftpads 16]]
+lappend coords {*}[to_grid -0.4 15]
+lappend coords {*}[to_grid 1 15]
+draw_pad_route $coords $wire_width
+
+# B3 vssa2
+set coords [list $leftpadx [lindex $leftpads 17]]
+lappend coords {*}[to_grid -0.4 15.8]
+lappend coords {*}[to_grid 0 15.8]
+lappend coords {*}[to_grid 1.3 15.8]
+lappend coords {*}[to_grid 2.2 15]
+lappend coords {*}[to_grid 3 15]
+draw_pad_route $coords $wire_width
+
+# C3 mprj_io[24]
+set coords [list $leftpadx [lindex $leftpads 20]]
+lappend coords {*}[to_grid 0 18]
+lappend coords {*}[to_grid 1.5 18]
+lappend coords {*}[to_grid 2 17.5]
+lappend coords {*}[to_grid 2 16.5]
+lappend coords {*}[to_grid 2.3 16.2]
+lappend coords {*}[to_grid 3.8 16.2]
+lappend coords {*}[to_grid 5 15]
+draw_pad_route $coords $wire_width
+
+# D3 mprj_io[13]
+set coords [list $rightpadx [lindex $rightpads 17]]
+lappend coords {*}[to_grid 12 16.2]
+lappend coords {*}[to_grid 8.2 16.2]
+lappend coords {*}[to_grid 7 15]
+draw_pad_route $coords $wire_width
+
+# E3 mprj_io[11]/flash2 io1
+set coords [list $rightpadx [lindex $rightpads 14]]
+lappend coords {*}[to_grid 12.6 14]
+lappend coords {*}[to_grid 10 14]
+lappend coords {*}[to_grid 9 15]
+draw_pad_route $coords $wire_width
+
+# F3 mprj_io[12]
+set coords [list $rightpadx [lindex $rightpads 15]]
+lappend coords {*}[to_grid 12.7 15]
+lappend coords {*}[to_grid 11 15]
+draw_pad_route $coords $wire_width
+
+# A2 vccd2
+set coords [list $leftpadx [lindex $leftpads 19]]
+lappend coords {*}[to_grid -0.4 17.5]
+lappend coords {*}[to_grid 0.5 17.5]
+lappend coords {*}[to_grid 1 17]
+draw_pad_route $coords $wire_width
+
+# B2 mprj_io[22]
+set coords [list [lindex $toppads 1] $toppady]
+lappend coords {*}[to_grid 2 19.7]
+lappend coords {*}[to_grid 2 18]
+lappend coords {*}[to_grid 3 17]
+draw_pad_route $coords $wire_width
+
+# C2 mprj_io[20]
+set coords [list [lindex $toppads 3] $toppady]
+lappend coords {*}[to_grid 4 19.7]
+lappend coords {*}[to_grid 4 18]
+lappend coords {*}[to_grid 5 17]
+draw_pad_route $coords $wire_width
+
+# D2 mprj_io[17]
+set coords [list [lindex $toppads 7] $toppady]
+lappend coords {*}[to_grid 8 19.7]
+lappend coords {*}[to_grid 8 18]
+lappend coords {*}[to_grid 7 17]
+draw_pad_route $coords $wire_width
+
+# E2 mprj_io[14]
+set coords [list $rightpadx [lindex $rightpads 19]]
+lappend coords {*}[to_grid 12.6 18.5]
+lappend coords {*}[to_grid 12 18.5]
+lappend coords {*}[to_grid 11.5 18]
+lappend coords {*}[to_grid 10 18]
+lappend coords {*}[to_grid 9 17]
+draw_pad_route $coords $wire_width
+
+# F2 vccd1
+set coords [list $rightpadx [lindex $rightpads 18]]
+lappend coords {*}[to_grid 12.5 17.5]
+lappend coords {*}[to_grid 11.5 17.5]
+lappend coords {*}[to_grid 11 17]
+draw_pad_route $coords $wire_width
+
+# A1 mprj_io[23]
+set coords [list [lindex $toppads 0] $toppady]
+lappend coords {*}[to_grid 1 19.7]
+lappend coords {*}[to_grid 1 19]
+draw_pad_route $coords $wire_width
+
+# B1 mprj_io[21]
+set coords [list [lindex $toppads 2] $toppady]
+lappend coords {*}[to_grid 3 19.7]
+lappend coords {*}[to_grid 3 19]
+draw_pad_route $coords $wire_width
+
+# C1 mprj_io[19]
+set coords [list [lindex $toppads 4] $toppady]
+lappend coords {*}[to_grid 5 19.7]
+lappend coords {*}[to_grid 5 19]
+draw_pad_route $coords $wire_width
+
+# D1 mrpj_io[18]
+set coords [list [lindex $toppads 6] $toppady]
+lappend coords {*}[to_grid 7 19.7]
+lappend coords {*}[to_grid 7 19]
+draw_pad_route $coords $wire_width
+
+# E1 mprj_io[16]
+set coords [list [lindex $toppads 8] $toppady]
+lappend coords {*}[to_grid 9.5 20]
+lappend coords {*}[to_grid 9.5 19.5]
+lappend coords {*}[to_grid 9 19]
+draw_pad_route $coords $wire_width
+
+# F1 mprj_io[15]
+set coords [list [lindex $toppads 10] $toppady]
+lappend coords {*}[to_grid 11 19.7]
+lappend coords {*}[to_grid 11 19]
+draw_pad_route $coords $wire_width
+
diff --git a/caravel/scripts/set_user_id.py b/caravel/scripts/set_user_id.py
new file mode 100644
index 0000000..6596bd0
--- /dev/null
+++ b/caravel/scripts/set_user_id.py
@@ -0,0 +1,348 @@
+#!/usr/bin/env python3
+# SPDX-FileCopyrightText: 2020 Efabless Corporation
+#
+# Licensed under the Apache License, Version 2.0 (the "License");
+# you may not use this file except in compliance with the License.
+# You may obtain a copy of the License at
+#
+#      http://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing, software
+# distributed under the License is distributed on an "AS IS" BASIS,
+# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+# See the License for the specific language governing permissions and
+# limitations under the License.
+# SPDX-License-Identifier: Apache-2.0
+
+#----------------------------------------------------------------------
+#
+# set_user_id.py ---
+#
+# Manipulate the magic database, GDS, and verilog source files for the
+# user_id_programming block to set the user ID number.
+#
+# The user ID number is a 32-bit value that is passed to this routine
+# as an 8-digit hex number.  If not given as an option, then the script
+# will look for the value of the key "project_id" in the info.yaml file
+# in the project top level directory
+#
+# user_id_programming layout map:
+# Positions marked (in microns) for value = 0.  For value = 1, move
+# the via 0.92um to the left.
+#
+# Layout grid is 0.46um x 0.34um with half-pitch offset (0.23um, 0.17um)
+#
+# Signal        Via position (um)
+# name		X      Y     
+#--------------------------------
+# mask_rev[0]   14.49  9.35
+# mask_rev[1]	16.33  9.35
+# mask_rev[2]	10.35 20.23
+# mask_rev[3]	 8.05  9.35
+# mask_rev[4]	28.29  9.35
+# mask_rev[5]	21.85 25.67
+# mask_rev[6]	 8.05 20.23
+# mask_rev[7]   20.47  9.35
+# mask_rev[8]   17.25 17.85
+# mask_rev[9]   25.53 12.07
+# mask_rev[10]  22.31 20.23
+# mask_rev[11]  13.11  9.35
+# mask_rev[12]	23.69 23.29
+# mask_rev[13]	24.15 12.07
+# mask_rev[14]	13.57 17.85
+# mask_rev[15]	23.23  6.97
+# mask_rev[16]	24.15 17.85
+# mask_rev[17]	 8.51 17.85
+# mask_rev[18]	23.69 20.23
+# mask_rev[19]	10.81 23.29
+# mask_rev[20]	14.95  6.97
+# mask_rev[21]	18.17 23.29
+# mask_rev[22]	21.39 17.85
+# mask_rev[23]	26.45 25.67
+# mask_rev[24]	 9.89 17.85
+# mask_rev[25]	15.87 17.85
+# mask_rev[26]	26.45 17.85
+# mask_rev[27]	 8.51  6.97
+# mask_rev[28]	10.81  9.35
+# mask_rev[29]	27.83 20.23
+# mask_rev[30]	16.33 23.29
+# mask_rev[31]	 8.05 14.79
+#----------------------------------------------------------------------
+
+import os
+import sys
+import re
+
+def usage():
+    print("Usage:")
+    print("set_user_id.py [<user_id_value>] [<path_to_project>]")
+    print("")
+    print("where:")
+    print("    <user_id_value>   is a character string of eight hex digits, and")
+    print("    <path_to_project> is the path to the project top level directory.")
+    print("")
+    print("  If <user_id_value> is not given, then it must exist in the info.yaml file.")
+    print("  If <path_to_project> is not given, then it is assumed to be the cwd.")
+    return 0
+
+if __name__ == '__main__':
+
+    # Coordinate pairs in microns for the zero position on each bit
+    mask_rev = (
+	(14.49,  9.35), (16.33,  9.35), (10.35, 20.23), ( 8.05,  9.35),
+	(28.29,  9.35), (21.85, 25.67), ( 8.05, 20.23), (20.47,  9.35),
+	(17.25, 17.85), (25.53, 12.07), (22.31, 20.23), (13.11,  9.35),
+	(23.69, 23.29), (24.15, 12.07), (13.57, 17.85), (23.23,  6.97),
+	(24.15, 17.85), ( 8.51, 17.85), (23.69, 20.23), (10.81, 23.29),
+	(14.95,  6.97), (18.17, 23.29), (21.39, 17.85), (26.45, 25.67),
+	( 9.89, 17.85), (15.87, 17.85), (26.45, 17.85), ( 8.51,  6.97),
+	(10.81,  9.35), (27.83, 20.23), (16.33, 23.29), ( 8.05, 14.79));
+
+    optionlist = []
+    arguments = []
+
+    debugmode = False
+    reportmode = False
+
+    for option in sys.argv[1:]:
+        if option.find('-', 0) == 0:
+            optionlist.append(option)
+        else:
+            arguments.append(option)
+
+    if len(arguments) > 2:
+        print("Wrong number of arguments given to set_user_id.py.")
+        usage()
+        sys.exit(0)
+
+    if '-debug' in optionlist:
+        debugmode = True
+    if '-report' in optionlist:
+        reportmode = True
+
+    user_id_value = None
+    user_project_path = None
+
+    if len(arguments) > 0:
+        user_id_value = arguments[0]
+
+        # Convert to binary
+        try:
+            user_id_int = int('0x' + user_id_value, 0)
+            user_id_bits = '{0:032b}'.format(user_id_int)
+        except:
+            user_project_path = arguments[0]
+
+    if len(arguments) == 0:
+        user_project_path = os.getcwd()
+    elif len(arguments) == 2:
+        user_project_path = arguments[1]
+    elif user_project_path == None:
+        user_project_path = arguments[0]
+    else:
+        user_project_path = os.getcwd()
+
+    if not os.path.isdir(user_project_path):
+        print('Error:  Project path "' + user_project_path + '" does not exist or is not readable.')
+        sys.exit(1)
+
+    # Check for valid directories
+
+    if not user_id_value:
+        if os.path.isfile(user_project_path + '/info.yaml'):
+            with open(user_project_path + '/info.yaml', 'r') as ifile:
+                infolines = ifile.read().splitlines()
+                for line in infolines:
+                    kvpair = line.split(':')
+                    if len(kvpair) == 2:
+                        key = kvpair[0].strip()
+                        value = kvpair[1].strip()
+                        if key == 'project_id':
+                            user_id_value = value.strip('"\'')
+                            break
+
+            if not user_id_value:
+                print('Error:  No project_id key:value pair found in project info.yaml.')
+                sys.exit(1)
+
+            try:
+                user_id_int = int('0x' + user_id_value, 0)
+                user_id_bits = '{0:032b}'.format(user_id_int)
+            except:
+                print('Error:  Cannot parse user ID "' + user_id_value + '" as an 8-digit hex number.')
+                sys.exit(1)
+
+        else:
+            print('Error:  No info.yaml file and no user ID argument given.')
+            sys.exit(1)
+
+    if reportmode:
+        print(str(user_id_int))
+        sys.exit(0)
+
+    print('Setting project user ID to: ' + user_id_value)
+
+    magpath = user_project_path + '/mag'
+    gdspath = user_project_path + '/gds'
+    vpath = user_project_path + '/verilog'
+    errors = 0 
+
+    if not os.path.isdir(gdspath):
+        print('No directory ' + gdspath + ' found (path to GDS).')
+        sys.exit(1)
+
+    if not os.path.isdir(vpath):
+        print('No directory ' + vpath + ' found (path to verilog).')
+        sys.exit(1)
+
+    if not os.path.isdir(magpath):
+        print('No directory ' + magpath + ' found (path to magic databases).')
+        sys.exit(1)
+
+    print('Step 1:  Modify GDS of the user_id_programming subcell')
+
+    # Bytes leading up to via position are:
+    viarec = "00 06 0d 02 00 43 00 06 0e 02 00 2c 00 2c 10 03 "
+    viabytes = bytes.fromhex(viarec)
+
+    # Read the GDS file.  If a backup was made of the zero-value
+    # program, then use it.
+
+    gdsbak = gdspath + '/user_id_prog_zero.gds'
+    gdsfile = gdspath + '/user_id_programming.gds'
+
+    if os.path.isfile(gdsbak):
+        with open(gdsbak, 'rb') as ifile:
+            gdsdata = ifile.read()
+    else:
+        with open(gdsfile, 'rb') as ifile:
+            gdsdata = ifile.read()
+
+    for i in range(0,32):
+        # Ignore any zero bits.
+        if user_id_bits[i] == '0':
+            continue
+
+        coords = mask_rev[i]
+        xum = coords[0]
+        yum = coords[1]
+
+        # Contact is 0.17 x 0.17, so add and subtract 0.085 to get
+        # the corner positions.
+
+        xllum = xum - 0.085
+        yllum = yum - 0.085
+        xurum = xum + 0.085
+        yurum = yum + 0.085
+ 
+        # Get the 4-byte hex values for the corner coordinates
+        xllnm = round(xllum * 1000)
+        yllnm = round(yllum * 1000)
+        xllhex = '{0:08x}'.format(xllnm)
+        yllhex = '{0:08x}'.format(yllnm)
+        xurnm = round(xurum * 1000)
+        yurnm = round(yurum * 1000)
+        xurhex = '{0:08x}'.format(xurnm)
+        yurhex = '{0:08x}'.format(yurnm)
+
+        # Magic's GDS output for vias always starts at the lower left
+        # corner and goes counterclockwise, repeating the first point.
+        viaoldposdata = viarec + xllhex + yllhex + xurhex + yllhex
+        viaoldposdata += xurhex + yurhex + xllhex + yurhex + xllhex + yllhex
+            
+        # For "one" bits, the X position is moved 0.92 microns to the left
+        newxllum = xllum - 0.92
+        newxurum = xurum - 0.92
+
+        # Get the 4-byte hex values for the new corner coordinates
+        newxllnm = round(newxllum * 1000)
+        newxllhex = '{0:08x}'.format(newxllnm)
+        newxurnm = round(newxurum * 1000)
+        newxurhex = '{0:08x}'.format(newxurnm)
+
+        vianewposdata = viarec + newxllhex + yllhex + newxurhex + yllhex
+        vianewposdata += newxurhex + yurhex + newxllhex + yurhex + newxllhex + yllhex
+
+        # Diagnostic
+        if debugmode:
+            print('Bit ' + str(i) + ':')
+            print('Via position ({0:3.2f}, {1:3.2f}) to ({2:3.2f}, {3:3.2f})'.format(xllum, yllum, xurum, yurum))
+            print('Old hex string = ' + viaoldposdata)
+            print('New hex string = ' + vianewposdata)
+
+        # Convert hex strings to byte arrays
+        viaoldbytedata = bytearray.fromhex(viaoldposdata)
+        vianewbytedata = bytearray.fromhex(vianewposdata)
+
+        # Replace the old data with the new
+        if viaoldbytedata not in gdsdata:
+            print('Error: via not found for bit position ' + str(i))
+            errors += 1 
+        else:
+            gdsdata = gdsdata.replace(viaoldbytedata, vianewbytedata)
+
+    if errors == 0:
+        # Keep a copy of the original 
+        if not os.path.isfile(gdsbak):
+            os.rename(gdsfile, gdsbak)
+
+        with open(gdsfile, 'wb') as ofile:
+            ofile.write(gdsdata)
+
+        print('Done!')
+            
+    else:
+        print('There were errors in processing.  No file written.')
+        print('Ending process.')
+        sys.exit(1)
+
+    print('Step 2:  Add user project ID parameter to verilog.')
+
+    changed = False
+    with open(vpath + '/rtl/caravel.v', 'r') as ifile:
+        vlines = ifile.read().splitlines()
+        outlines = []
+        for line in vlines:
+            oline = re.sub("parameter USER_PROJECT_ID = 32'h[0-9A-F]+;",
+			"parameter USER_PROJECT_ID = 32'h" + user_id_value + ";",
+			line)
+            if oline != line:
+                changed = True
+            outlines.append(oline)
+
+    if changed:
+        with open(vpath + '/rtl/caravel.v', 'w') as ofile:
+            for line in outlines:
+                print(line, file=ofile)
+            print('Done!')
+    else:
+        print('Error:  No substitutions done on verilog/rtl/caravel.v.')
+        print('Ending process.')
+        sys.exit(1)
+
+    print('Step 3:  Add user project ID text to top level layout.')
+
+    with open(magpath + '/user_id_textblock.mag', 'r') as ifile:
+        maglines = ifile.read().splitlines()
+        outlines = []
+        digit = 0
+        for line in maglines:
+            if 'alphaX_' in line:
+                dchar = user_id_value[digit].upper()
+                oline = re.sub('alpha_[0-9A-F]', 'alpha_' + dchar, line)
+                outlines.append(oline)
+                digit += 1
+            else:
+                outlines.append(line)
+
+    if digit == 8:
+        with open(magpath + '/user_id_textblock.mag', 'w') as ofile:
+            for line in outlines:
+                print(line, file=ofile)
+        print('Done!')
+    elif digit == 0:
+        print('Error:  No digits were replaced in the layout.')
+    else:
+        print('Error:  Only ' + str(digit) + ' digits were replaced in the layout.')
+
+    sys.exit(0)
diff --git a/caravel/spi/lvs/run_lvs.sh b/caravel/spi/lvs/run_lvs.sh
new file mode 100644
index 0000000..25c27a1
--- /dev/null
+++ b/caravel/spi/lvs/run_lvs.sh
@@ -0,0 +1,20 @@
+#!/bin/sh
+# SPDX-FileCopyrightText: 2020 Efabless Corporation
+#
+# Licensed under the Apache License, Version 2.0 (the "License");
+# you may not use this file except in compliance with the License.
+# You may obtain a copy of the License at
+#
+#      http://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing, software
+# distributed under the License is distributed on an "AS IS" BASIS,
+# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+# See the License for the specific language governing permissions and
+# limitations under the License.
+# SPDX-License-Identifier: Apache-2.0
+
+
+NETGEN_SETUP=$PDK_ROOT/sky130A/libs.tech/netgen/sky130A_setup.tcl
+
+netgen -batch lvs "$1 $3" "$2 $3" ${NETGEN_SETUP} $2_comp.out -json | tee $2_comp_lvs.log
diff --git a/caravel/utils/MAGIC.txt b/caravel/utils/MAGIC.txt
new file mode 100644
index 0000000..78b4d56
--- /dev/null
+++ b/caravel/utils/MAGIC.txt
@@ -0,0 +1,31 @@
+# SPDX-FileCopyrightText: 2020 Efabless Corporation
+#
+# Licensed under the Apache License, Version 2.0 (the "License");
+# you may not use this file except in compliance with the License.
+# You may obtain a copy of the License at
+#
+#      http://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing, software
+# distributed under the License is distributed on an "AS IS" BASIS,
+# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+# See the License for the specific language governing permissions and
+# limitations under the License.
+#
+# SPDX-License-Identifier: Apache-2.0
+
+####
+
+1) You must set the PDK_ROOT variable
+
+export PDK_ROOT=~/foss/pdks/open_pdks/sky130;
+export PDKPATH=$PDK_ROOT/sky130A ;
+
+2) Useful misc utils
+
+
+
+load caravel -dereference
+drc style drc(full)
+drc why
+drc find 10 ; findbox zoom
diff --git a/caravel/utils/README.txt b/caravel/utils/README.txt
new file mode 100644
index 0000000..78b4d56
--- /dev/null
+++ b/caravel/utils/README.txt
@@ -0,0 +1,31 @@
+# SPDX-FileCopyrightText: 2020 Efabless Corporation
+#
+# Licensed under the Apache License, Version 2.0 (the "License");
+# you may not use this file except in compliance with the License.
+# You may obtain a copy of the License at
+#
+#      http://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing, software
+# distributed under the License is distributed on an "AS IS" BASIS,
+# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+# See the License for the specific language governing permissions and
+# limitations under the License.
+#
+# SPDX-License-Identifier: Apache-2.0
+
+####
+
+1) You must set the PDK_ROOT variable
+
+export PDK_ROOT=~/foss/pdks/open_pdks/sky130;
+export PDKPATH=$PDK_ROOT/sky130A ;
+
+2) Useful misc utils
+
+
+
+load caravel -dereference
+drc style drc(full)
+drc why
+drc find 10 ; findbox zoom
diff --git a/caravel/utils/addmpwseal.tcl b/caravel/utils/addmpwseal.tcl
new file mode 100644
index 0000000..b562f93
--- /dev/null
+++ b/caravel/utils/addmpwseal.tcl
@@ -0,0 +1,25 @@
+# SPDX-FileCopyrightText: 2020 Efabless Corporation
+#
+# Licensed under the Apache License, Version 2.0 (the "License");
+# you may not use this file except in compliance with the License.
+# You may obtain a copy of the License at
+#
+#      http://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing, software
+# distributed under the License is distributed on an "AS IS" BASIS,
+# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+# See the License for the specific language governing permissions and
+# limitations under the License.
+# SPDX-License-Identifier: Apache-2.0
+
+drc off
+gds readonly true
+gds rescale false
+gds read ../gds/sram_1rw1r_32_256_8_sky130_lp1.gds
+load ./caravel.mag
+select top cell
+move origin -7.165um -7.120um
+box position 0 0
+getcell advSeal_6um_gen
+gds write caravel.mpw.gds
diff --git a/caravel/utils/apply_caravel.sh b/caravel/utils/apply_caravel.sh
new file mode 100644
index 0000000..1a922cf
--- /dev/null
+++ b/caravel/utils/apply_caravel.sh
@@ -0,0 +1,44 @@
+#!/bin/bash
+# SPDX-FileCopyrightText: 2020 Efabless Corporation
+#
+# Licensed under the Apache License, Version 2.0 (the "License");
+# you may not use this file except in compliance with the License.
+# You may obtain a copy of the License at
+#
+#      http://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing, software
+# distributed under the License is distributed on an "AS IS" BASIS,
+# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+# See the License for the specific language governing permissions and
+# limitations under the License.
+# SPDX-License-Identifier: Apache-2.0
+
+# To use: sh apply_caravel.sh <target_project_path> <template_caravel_path>
+
+target_project=$1
+original_caravel=$2
+
+find $original_caravel/def/* -type f ! -name "user_project_wrapper.def" ! -name "user_proj_example.def" -exec cp {} $target_project/def \;
+find $original_caravel/lef/* -type f ! -name "user_project_wrapper.lef" ! -name "user_proj_example.lef" -exec cp {} $target_project/lef \;
+find $original_caravel/gds/* -type f ! -name "user_project_wrapper.gds.gz" ! -name "user_proj_example.gds.gz" ! -name "user_project_wrapper.gds" ! -name "user_proj_example.gds" -exec cp {} $target_project/gds \;
+find $original_caravel/mag/* -type f ! -name "user_project_wrapper.mag" ! -name "user_proj_example.mag" -exec cp {} $target_project/mag \;
+cp $original_caravel/mag/.magicrc $target_project/mag/
+mkdir -p $target_project/mag/hexdigits/
+mv $target_project/mag/alpha_*.mag $target_project/mag/hexdigits/
+cp $original_caravel/maglef/* $target_project/maglef
+cp -r $original_caravel/ngspice/digital_pll $target_project/ngspice/digital_pll
+cp -r $original_caravel/ngspice/simple_por $target_project/ngspice/simple_por
+cp -r $original_caravel/scripts $target_project/scripts
+find $original_caravel/spi/lvs/* -type f ! -name "user_project_wrapper.spice" ! -name "user_proj_example.spice" -exec cp {} $target_project/spi/lvs/ \;
+cp -r $original_caravel/utils $target_project/utils
+find $original_caravel/verilog/rtl/* -type f ! -name "user_project_wrapper.v" ! -name "user_proj_example.v" -exec cp {} $target_project/verilog/rtl/ \;
+find $original_caravel/verilog/gl/* -type f ! -name "user_project_wrapper.v" ! -name "user_proj_example.v" -exec cp {} $target_project/verilog/gl/ \;
+cp $original_caravel/verilog/stubs/*.v $target_project/verilog/stubs/
+cp -r $original_caravel/verilog/dv/caravel $target_project/verilog/dv/caravel
+cp -r $original_caravel/verilog/dv/wb_utests $target_project/verilog/dv/wb_utests
+cp $original_caravel/verilog/dv/dummy_slave.v $target_project/verilog/dv/dummy_slave.v
+
+echo "You'll have to manually copy the openlane/user_project_wrapper configs based on your preference."
+echo "You'll have to manually copy the openlane/Makefile based on your preference."
+echo "You'll have to manually copy the Makefile based on your preference."
\ No newline at end of file
diff --git a/caravel/utils/core_scripts/README.md b/caravel/utils/core_scripts/README.md
new file mode 100644
index 0000000..b14c1db
--- /dev/null
+++ b/caravel/utils/core_scripts/README.md
@@ -0,0 +1,20 @@
+<!---
+# SPDX-FileCopyrightText: 2020 Efabless Corporation
+#
+# Licensed under the Apache License, Version 2.0 (the "License");
+# you may not use this file except in compliance with the License.
+# You may obtain a copy of the License at
+#
+#      http://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing, software
+# distributed under the License is distributed on an "AS IS" BASIS,
+# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+# See the License for the specific language governing permissions and
+# limitations under the License.
+#
+# SPDX-License-Identifier: Apache-2.0
+-->
+# What is this?
+
+Core scripts are doing the actual work, scripts under ../scripts are the ones that should be used.
\ No newline at end of file
diff --git a/caravel/utils/core_scripts/magic-drc.sh b/caravel/utils/core_scripts/magic-drc.sh
new file mode 100644
index 0000000..5f5068d
--- /dev/null
+++ b/caravel/utils/core_scripts/magic-drc.sh
@@ -0,0 +1,54 @@
+#!/bin/bash
+# SPDX-FileCopyrightText: 2020 Efabless Corporation
+#
+# Licensed under the Apache License, Version 2.0 (the "License");
+# you may not use this file except in compliance with the License.
+# You may obtain a copy of the License at
+#
+#      http://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing, software
+# distributed under the License is distributed on an "AS IS" BASIS,
+# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+# See the License for the specific language governing permissions and
+# limitations under the License.
+# SPDX-License-Identifier: Apache-2.0
+
+# To call: ./magic-drc.sh <target_path> <design_name> <pdk-root> <target-type> <pdk-name> <output_path>
+
+export TARGET_DIR=$1
+export DESIGN_NAME=$2
+export PDK_ROOT=$3
+export TARGET_TYPE=$4
+export PDK=$5
+export OUT_DIR=$6
+export TCL_CALL_PATH=${7:-$(pwd)}
+
+echo "Running Magic..."
+export MAGIC_MAGICRC=$PDK_ROOT/$PDK/libs.tech/magic/sky130A.magicrc
+
+magic \
+    -noconsole \
+    -dnull \
+    -rcfile $MAGIC_MAGICRC \
+    $TCL_CALL_PATH/magic-drc.tcl \
+    </dev/null \
+    |& tee $OUT_DIR/magic_drc.log
+
+TEST=$OUT_DIR/$DESIGN_NAME.magic.drc
+
+crashSignal=$(find $TEST)
+if ! [[ $crashSignal ]]; then echo "DRC Check FAILED"; exit -1; fi
+
+
+Test_Magic_violations=$(grep "COUNT: " $TEST -s | tail -1 | sed -r 's/[^0-9]*//g')
+if ! [[ $Test_Magic_violations ]]; then Test_Magic_violations=-1; fi
+if [ $Test_Magic_violations -ne -1 ]; then Test_Magic_violations=$(((Test_Magic_violations+3)/4)); fi
+
+echo "Test # of DRC Violations:"
+echo $Test_Magic_violations
+
+if [ 0 -ne $Test_Magic_violations ]; then echo "DRC Check FAILED"; exit -1; fi
+
+echo "DRC Check Passed"
+exit 0
diff --git a/caravel/utils/core_scripts/magic-drc.tcl b/caravel/utils/core_scripts/magic-drc.tcl
new file mode 100644
index 0000000..6768d3c
--- /dev/null
+++ b/caravel/utils/core_scripts/magic-drc.tcl
@@ -0,0 +1,74 @@
+# SPDX-FileCopyrightText: 2020 Efabless Corporation
+#
+# Licensed under the Apache License, Version 2.0 (the "License");
+# you may not use this file except in compliance with the License.
+# You may obtain a copy of the License at
+#
+#      http://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing, software
+# distributed under the License is distributed on an "AS IS" BASIS,
+# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+# See the License for the specific language governing permissions and
+# limitations under the License.
+# SPDX-License-Identifier: Apache-2.0
+
+if { $::env(TARGET_TYPE) == "gds"} {
+	gds read $::env(TARGET_DIR)/$::env(DESIGN_NAME).gds
+} else {
+	if { $::env(TARGET_TYPE) == "mag" } {
+		load $::env(TARGET_DIR)/$::env(DESIGN_NAME).mag
+	} else {
+		def read $::env(TARGET_DIR)/$::env(DESIGN_NAME).def
+	}
+}
+
+set fout [open $::env(OUT_DIR)/$::env(DESIGN_NAME).magic.drc w]
+set oscale [cif scale out]
+set cell_name $::env(DESIGN_NAME)
+magic::suspendall
+puts stdout "\[INFO\]: Loading $cell_name\n"
+flush stdout
+load $cell_name
+select top cell
+drc euclidean on
+drc style drc(full)
+drc check
+set drcresult [drc listall why]
+
+
+set count 0
+puts $fout "$cell_name"
+puts $fout "----------------------------------------"
+foreach {errtype coordlist} $drcresult {
+	puts $fout $errtype
+	puts $fout "----------------------------------------"
+	foreach coord $coordlist {
+	    set bllx [expr {$oscale * [lindex $coord 0]}]
+	    set blly [expr {$oscale * [lindex $coord 1]}]
+	    set burx [expr {$oscale * [lindex $coord 2]}]
+	    set bury [expr {$oscale * [lindex $coord 3]}]
+	    set coords [format " %.3f %.3f %.3f %.3f" $bllx $blly $burx $bury]
+	    puts $fout "$coords"
+	    set count [expr {$count + 1} ]
+	}
+	puts $fout "----------------------------------------"
+}
+
+puts $fout "\[INFO\]: COUNT: $count"
+puts $fout "\[INFO\]: Should be divided by 3 or 4"
+
+puts $fout ""
+close $fout
+
+puts stdout "\[INFO\]: COUNT: $count"
+puts stdout "\[INFO\]: Should be divided by 3 or 4"
+puts stdout "\[INFO\]: DRC Checking DONE ($::env(OUT_DIR)/$::env(DESIGN_NAME).magic.drc)"
+flush stdout
+
+puts stdout "\[INFO\]: Saving mag view with DRC errors($::env(OUT_DIR)/$::env(DESIGN_NAME).magic.drc.mag)"
+# WARNING: changes the name of the cell; keep as last step
+save $::env(OUT_DIR)/$::env(DESIGN_NAME).magic.drc.mag
+puts stdout "\[INFO\]: Saved"
+
+exit 0
diff --git a/caravel/utils/core_scripts/magic-ext.sh b/caravel/utils/core_scripts/magic-ext.sh
new file mode 100644
index 0000000..68bfc39
--- /dev/null
+++ b/caravel/utils/core_scripts/magic-ext.sh
@@ -0,0 +1,36 @@
+#!/bin/bash
+# SPDX-FileCopyrightText: 2020 Efabless Corporation
+#
+# Licensed under the Apache License, Version 2.0 (the "License");
+# you may not use this file except in compliance with the License.
+# You may obtain a copy of the License at
+#
+#      http://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing, software
+# distributed under the License is distributed on an "AS IS" BASIS,
+# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+# See the License for the specific language governing permissions and
+# limitations under the License.
+# SPDX-License-Identifier: Apache-2.0
+
+# To call: ./magic-ext.sh <target_path> <design_name> <pdk-root> <target-type> <pdk-name> <output_path>
+
+export TARGET_DIR=$1
+export DESIGN_NAME=$2
+export PDK_ROOT=$3
+export TARGET_TYPE=$4
+export PDK=$5
+export OUT_DIR=$6
+export TCL_CALL_PATH=${7:-$(pwd)}
+
+echo "Running Magic..."
+export MAGIC_MAGICRC=$PDK_ROOT/$PDK/libs.tech/magic/sky130A.magicrc
+
+magic \
+    -noconsole \
+    -dnull \
+    -rcfile $MAGIC_MAGICRC \
+    $TCL_CALL_PATH/magic-ext.tcl \
+    </dev/null \
+    |& tee $OUT_DIR/magic_ext.log
diff --git a/caravel/utils/core_scripts/magic-ext.tcl b/caravel/utils/core_scripts/magic-ext.tcl
new file mode 100644
index 0000000..5a05dcb
--- /dev/null
+++ b/caravel/utils/core_scripts/magic-ext.tcl
@@ -0,0 +1,44 @@
+#!/usr/bin/tclsh
+# SPDX-FileCopyrightText: 2020 Efabless Corporation
+#
+# Licensed under the Apache License, Version 2.0 (the "License");
+# you may not use this file except in compliance with the License.
+# You may obtain a copy of the License at
+#
+#      http://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing, software
+# distributed under the License is distributed on an "AS IS" BASIS,
+# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+# See the License for the specific language governing permissions and
+# limitations under the License.
+# SPDX-License-Identifier: Apache-2.0
+
+
+puts "Performing Spice Extractions..."
+
+if { ![file isdirectory $::env(OUT_DIR)] } {
+	exec mkdir $::env(OUT_DIR)/
+}
+
+
+if { $::env(TARGET_TYPE) == "gds"} {
+	gds read $::env(TARGET_DIR)/$::env(DESIGN_NAME).gds
+} else {
+	if { $::env(TARGET_TYPE) == "mag" } {
+		load $::env(TARGET_DIR)/$::env(DESIGN_NAME).mag
+	} else {
+		def read $::env(TARGET_DIR)/$::env(DESIGN_NAME).def
+	}
+}
+
+load $::env(DESIGN_NAME) -dereference
+cd $::env(OUT_DIR)/
+extract do local
+# extract warn all
+extract
+ext2spice lvs
+ext2spice $::env(DESIGN_NAME).ext
+feedback save $::env(OUT_DIR)/magic_extraction_feedback.txt
+
+puts "Done!"
\ No newline at end of file
diff --git a/caravel/utils/drc-def-sky130A.sh b/caravel/utils/drc-def-sky130A.sh
new file mode 100644
index 0000000..671b14a
--- /dev/null
+++ b/caravel/utils/drc-def-sky130A.sh
@@ -0,0 +1,29 @@
+#!/bin/bash
+# SPDX-FileCopyrightText: 2020 Efabless Corporation
+#
+# Licensed under the Apache License, Version 2.0 (the "License");
+# you may not use this file except in compliance with the License.
+# You may obtain a copy of the License at
+#
+#      http://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing, software
+# distributed under the License is distributed on an "AS IS" BASIS,
+# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+# See the License for the specific language governing permissions and
+# limitations under the License.
+# SPDX-License-Identifier: Apache-2.0
+
+# To call: ./drc-def-sky130A.sh <target_path> <design_name> <pdk-root> [<output_path> default is <target_path>/results/]
+
+export TARGET_DIR=$1
+export DESIGN_NAME=$2
+export PDK_ROOT=$3
+export OUT_DIR=${4:-$TARGET_DIR/results/}
+export TCL_CALL_PATH=$(pwd)/core_scripts
+
+if ! [[ -d "$OUT_DIR" ]]
+then
+    mkdir $OUT_DIR
+fi
+bash ./core_scripts/magic-drc.sh $TARGET_DIR $DESIGN_NAME $PDK_ROOT "def" "sky130A" $OUT_DIR $TCL_CALL_PATH
diff --git a/caravel/utils/drc-gds-sky130A.sh b/caravel/utils/drc-gds-sky130A.sh
new file mode 100644
index 0000000..4c1d6d8
--- /dev/null
+++ b/caravel/utils/drc-gds-sky130A.sh
@@ -0,0 +1,30 @@
+#!/bin/bash
+# SPDX-FileCopyrightText: 2020 Efabless Corporation
+#
+# Licensed under the Apache License, Version 2.0 (the "License");
+# you may not use this file except in compliance with the License.
+# You may obtain a copy of the License at
+#
+#      http://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing, software
+# distributed under the License is distributed on an "AS IS" BASIS,
+# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+# See the License for the specific language governing permissions and
+# limitations under the License.
+# SPDX-License-Identifier: Apache-2.0
+
+# To call: ./drc-gds-sky130A.sh <target_path> <design_name> <pdk-root> [<output_path> default is <target_path>/results/]
+
+export TARGET_DIR=$1
+export DESIGN_NAME=$2
+export PDK_ROOT=$3
+export OUT_DIR=${4:-$TARGET_DIR/results/}
+export TCL_CALL_PATH=$(pwd)/core_scripts
+
+if ! [[ -d "$OUT_DIR" ]]
+then
+    mkdir $OUT_DIR
+fi
+
+bash ./core_scripts/magic-drc.sh $TARGET_DIR $DESIGN_NAME $PDK_ROOT "gds" "sky130A" $OUT_DIR $TCL_CALL_PATH
diff --git a/caravel/utils/drc-mag-sky130A.sh b/caravel/utils/drc-mag-sky130A.sh
new file mode 100644
index 0000000..2bbecd3
--- /dev/null
+++ b/caravel/utils/drc-mag-sky130A.sh
@@ -0,0 +1,29 @@
+#!/bin/bash
+# SPDX-FileCopyrightText: 2020 Efabless Corporation
+#
+# Licensed under the Apache License, Version 2.0 (the "License");
+# you may not use this file except in compliance with the License.
+# You may obtain a copy of the License at
+#
+#      http://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing, software
+# distributed under the License is distributed on an "AS IS" BASIS,
+# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+# See the License for the specific language governing permissions and
+# limitations under the License.
+# SPDX-License-Identifier: Apache-2.0
+
+# To call: ./drc-mag-sky130A.sh <target_path> <design_name> <pdk-root> [<output_path> default is <target_path>/results/]
+
+export TARGET_DIR=$1
+export DESIGN_NAME=$2
+export PDK_ROOT=$3
+export OUT_DIR=${4:-$TARGET_DIR/results/}
+export TCL_CALL_PATH=$(pwd)/core_scripts
+
+if ! [[ -d "$OUT_DIR" ]]
+then
+    mkdir $OUT_DIR
+fi
+bash ./core_scripts/magic-drc.sh $TARGET_DIR $DESIGN_NAME $PDK_ROOT "mag" "sky130A" $OUT_DIR $TCL_CALL_PATH
diff --git a/caravel/utils/erase_box.sh b/caravel/utils/erase_box.sh
new file mode 100644
index 0000000..7636e42
--- /dev/null
+++ b/caravel/utils/erase_box.sh
@@ -0,0 +1,42 @@
+#!/bin/bash
+# SPDX-FileCopyrightText: 2020 Efabless Corporation
+#
+# Licensed under the Apache License, Version 2.0 (the "License");
+# you may not use this file except in compliance with the License.
+# You may obtain a copy of the License at
+#
+#      http://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing, software
+# distributed under the License is distributed on an "AS IS" BASIS,
+# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+# See the License for the specific language governing permissions and
+# limitations under the License.
+# SPDX-License-Identifier: Apache-2.0
+: ${1?"Usage: $0 file.gds llx lly urx ury"}
+: ${2?"Usage: $0 file.gds llx lly urx ury"}
+: ${3?"Usage: $0 file.gds llx lly urx ury"}
+: ${4?"Usage: $0 file.gds llx lly urx ury"}
+: ${5?"Usage: $0 file.gds llx lly urx ury"}
+: ${PDK_ROOT?"You need to export PDK_ROOT"}
+
+
+export PDK=sky130A
+
+export MAGIC_MAGICRC=$PDK_ROOT/$PDK/libs.tech/magic/$PDK.magicrc
+
+MAGTYPE=mag magic -rcfile $MAGIC_MAGICRC -dnull -noconsole  <<EOF
+echo $MAGTYPE
+tech unlock *
+gds read $1
+box $2um $3um $4um $5um
+erase
+select area
+delete
+#### REVISE THIS:
+select top cell
+erase labels
+####
+gds write ${1%.*}_erased.gds
+EOF
+ls ${1%.*}_erased.gds
diff --git a/caravel/utils/examples/README.md b/caravel/utils/examples/README.md
new file mode 100644
index 0000000..10f7a37
--- /dev/null
+++ b/caravel/utils/examples/README.md
@@ -0,0 +1,19 @@
+<!---
+# SPDX-FileCopyrightText: 2020 Efabless Corporation
+#
+# Licensed under the Apache License, Version 2.0 (the "License");
+# you may not use this file except in compliance with the License.
+# You may obtain a copy of the License at
+#
+#      http://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing, software
+# distributed under the License is distributed on an "AS IS" BASIS,
+# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+# See the License for the specific language governing permissions and
+# limitations under the License.
+#
+# SPDX-License-Identifier: Apache-2.0
+-->
+This folder contains miscelleneous useful scripts
+THIS IS STILL WORK IN PROGRESSS - SUGGESTIONS ARE WELCOME THROUGH ISSUES
diff --git a/caravel/utils/examples/addmpwseal.tcl b/caravel/utils/examples/addmpwseal.tcl
new file mode 100644
index 0000000..79e4b9e
--- /dev/null
+++ b/caravel/utils/examples/addmpwseal.tcl
@@ -0,0 +1,26 @@
+# SPDX-FileCopyrightText: 2020 Efabless Corporation
+#
+# Licensed under the Apache License, Version 2.0 (the "License");
+# you may not use this file except in compliance with the License.
+# You may obtain a copy of the License at
+#
+#      http://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing, software
+# distributed under the License is distributed on an "AS IS" BASIS,
+# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+# See the License for the specific language governing permissions and
+# limitations under the License.
+# SPDX-License-Identifier: Apache-2.0
+
+drc off
+gds readonly true
+gds read ../gds/sram_1rw1r_32_256_8_sky130_lp1.gds
+load openram_tc_1kb.mag
+select top cell
+move origin -1015um -1272.5um
+box position 0 0
+getcell advSeal_6um_gen
+save
+gds write ../gds/openram_tc_1kb.gds
+
diff --git a/caravel/utils/examples/create-project.sh b/caravel/utils/examples/create-project.sh
new file mode 100644
index 0000000..5b5b69c
--- /dev/null
+++ b/caravel/utils/examples/create-project.sh
@@ -0,0 +1,38 @@
+#!/bin/sh
+# SPDX-FileCopyrightText: 2020 Efabless Corporation
+#
+# Licensed under the Apache License, Version 2.0 (the "License");
+# you may not use this file except in compliance with the License.
+# You may obtain a copy of the License at
+#
+#      http://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing, software
+# distributed under the License is distributed on an "AS IS" BASIS,
+# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+# See the License for the specific language governing permissions and
+# limitations under the License.
+# SPDX-License-Identifier: Apache-2.0
+
+cat <<'EOT' > .gitignore
+.DS_Store
+*.vcd
+*.raw
+*.vvp
+a.out
+EOT
+mkdir scripts		; echo "This folder contains miscelleneous useful scripts" > scripts/README.md 
+mkdir def		; echo "This folder contains *.def files related to this project" > def/README.md 
+mkdir gds		; echo "This folder contains *.gds files related to this project" > gds/README.md 
+mkdir verilog		; echo "This folder contains *.v   files related to this project" > verilog/README.md 
+mkdir mag		; echo "This folder contains *.mag files related to this project" > mag/README.md 
+mkdir lef		; echo "This folder contains *.lef files related to this project" > lef/README.md 
+mkdir macros		; echo "This folder contains subcell & macro files related to this project" > macros/README.md 
+mkdir doc		; echo "This folder contains documents related to this project" > doc/README.md 
+mkdir ngspice		; echo "This folder contains ngspice related files related to this project" > ngspice/README.md 
+mkdir openlane		; echo "This folder contains openlane related files related to this project" > openlane/README.md 
+mkdir pkg		; echo "This folder contains packaging-related files related to this project" > pkg/README.md
+mkdir test		; echo "This folder contains test-related files related to this project" > test/README.md
+mkdir xspice		; echo "This folder contains xspice files related to this project" > xspice/README.md
+mkdir spi		; echo "This folder contains *.spi files related to this project" > spi/README.md
+mkdir qflow		; echo "This folder contains qflow-related files related to this project" > qflow/README.md
diff --git a/caravel/utils/examples/dot.magicrc b/caravel/utils/examples/dot.magicrc
new file mode 100644
index 0000000..42f2fb2
--- /dev/null
+++ b/caravel/utils/examples/dot.magicrc
@@ -0,0 +1,65 @@
+# SPDX-FileCopyrightText: 2020 Efabless Corporation
+#
+# Licensed under the Apache License, Version 2.0 (the "License");
+# you may not use this file except in compliance with the License.
+# You may obtain a copy of the License at
+#
+#      http://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing, software
+# distributed under the License is distributed on an "AS IS" BASIS,
+# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+# See the License for the specific language governing permissions and
+# limitations under the License.
+#
+# SPDX-License-Identifier: Apache-2.0
+
+puts stdout "Sourcing design .magicrc for technology sky130A ..."
+
+# Put grid on 0.005 pitch.  This is important, as some commands don't
+# rescale the grid automatically (such as lef read?).
+
+set scalefac [tech lambda]
+if {[lindex $scalefac 1] < 2} {
+    scalegrid 1 2
+}
+
+# drc off
+drc euclidean on
+
+# default pdk 
+# set SW_PDK_ROOT "/ef/tech/SW.2"
+set PDK "sky130A"
+set SCL_VARIANT "sky130_fd_sc_hd"
+set IO_VARIANT "sky130_fd_io"
+set PDKPATH "$::env(SW_PDK_ROOT)/$PDK"
+
+# loading technology
+tech load "$PDKPATH/libs.tech/magic/current/$PDK.tech"
+
+# load device generator
+source "$PDKPATH/libs.tech/magic/current/$PDK.tcl"
+
+
+# load bind keys (optional)
+source "$PDKPATH/libs.tech/magic/current/$PDK-BindKeys"
+
+# set units to lambda grid 
+snap lambda
+
+# add path to reference cells
+set MAGPATH "$PDKPATH/libs.ref/$SCL_VARIANT/mag/*.mag"
+
+
+addpath "$PDKPATH/libs.ref/sky130_fd_pr_base/mag"
+addpath "$PDKPATH/libs.ref/$IO_VARIANT/mag"
+addpath "$PDKPATH/libs.ref/$SCL_VARIANT/mag"
+
+# addpath ${MAGPATH}/s8fmlt
+
+# add path to GDS cells
+
+# add path to IP from catalog.  This procedure defined in the PDK script.
+catch {magic::query_mylib_ip}
+# add path to local IP from user design space.  Defined in the PDK script.
+catch {magic::query_my_projects}
diff --git a/caravel/utils/examples/drc-mag.sh b/caravel/utils/examples/drc-mag.sh
new file mode 100644
index 0000000..7229f45
--- /dev/null
+++ b/caravel/utils/examples/drc-mag.sh
@@ -0,0 +1,40 @@
+#!/bin/bash
+# SPDX-FileCopyrightText: 2020 Efabless Corporation
+#
+# Licensed under the Apache License, Version 2.0 (the "License");
+# you may not use this file except in compliance with the License.
+# You may obtain a copy of the License at
+#
+#      http://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing, software
+# distributed under the License is distributed on an "AS IS" BASIS,
+# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+# See the License for the specific language governing permissions and
+# limitations under the License.
+# SPDX-License-Identifier: Apache-2.0
+
+
+export MAGTYPE=mag ;
+export BASE=/home/mk/zooz/ ;
+export PDKPATH=$BASE/pdks/ef-skywater-s8/EFS8A ;
+
+magic -dnull -noconsole -rcfile $PDKPATH/libs.tech/magic/current/EFS8A.magicrc <<EOF
+gds polygon subcell true
+gds warning default
+gds read $1.gds
+load $1
+cellname delete \(UNNAMED\)
+writeall force
+select top cell
+expand
+drc on
+drc euclidean on
+drc check
+drc catchup
+drc listall 
+drc listall why
+drc count total
+drc count
+quit -noprompt
+EOF
diff --git a/caravel/utils/examples/drc-maglef.sh b/caravel/utils/examples/drc-maglef.sh
new file mode 100644
index 0000000..42f622f
--- /dev/null
+++ b/caravel/utils/examples/drc-maglef.sh
@@ -0,0 +1,40 @@
+#!/bin/bash
+# SPDX-FileCopyrightText: 2020 Efabless Corporation
+#
+# Licensed under the Apache License, Version 2.0 (the "License");
+# you may not use this file except in compliance with the License.
+# You may obtain a copy of the License at
+#
+#      http://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing, software
+# distributed under the License is distributed on an "AS IS" BASIS,
+# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+# See the License for the specific language governing permissions and
+# limitations under the License.
+# SPDX-License-Identifier: Apache-2.0
+
+
+export MAGTYPE=maglef ;
+export BASE=/home/mk/zooz/ ;
+export PDKPATH=$BASE/pdks/ef-skywater-s8/EFS8A ;
+
+magic -dnull -noconsole -rcfile $PDKPATH/libs.tech/magic/current/EFS8A.magicrc <<EOF
+gds polygon subcell true
+gds warning default
+gds read $1.gds
+load $1
+cellname delete \(UNNAMED\)
+writeall force
+select top cell
+expand
+drc on
+drc euclidean on
+drc check
+drc catchup
+drc listall 
+drc listall why
+drc count total
+drc count
+quit -noprompt
+EOF
diff --git a/caravel/utils/examples/drc.sh b/caravel/utils/examples/drc.sh
new file mode 100644
index 0000000..7229f45
--- /dev/null
+++ b/caravel/utils/examples/drc.sh
@@ -0,0 +1,40 @@
+#!/bin/bash
+# SPDX-FileCopyrightText: 2020 Efabless Corporation
+#
+# Licensed under the Apache License, Version 2.0 (the "License");
+# you may not use this file except in compliance with the License.
+# You may obtain a copy of the License at
+#
+#      http://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing, software
+# distributed under the License is distributed on an "AS IS" BASIS,
+# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+# See the License for the specific language governing permissions and
+# limitations under the License.
+# SPDX-License-Identifier: Apache-2.0
+
+
+export MAGTYPE=mag ;
+export BASE=/home/mk/zooz/ ;
+export PDKPATH=$BASE/pdks/ef-skywater-s8/EFS8A ;
+
+magic -dnull -noconsole -rcfile $PDKPATH/libs.tech/magic/current/EFS8A.magicrc <<EOF
+gds polygon subcell true
+gds warning default
+gds read $1.gds
+load $1
+cellname delete \(UNNAMED\)
+writeall force
+select top cell
+expand
+drc on
+drc euclidean on
+drc check
+drc catchup
+drc listall 
+drc listall why
+drc count total
+drc count
+quit -noprompt
+EOF
diff --git a/caravel/utils/examples/edit.tcl b/caravel/utils/examples/edit.tcl
new file mode 100644
index 0000000..f1766ad
--- /dev/null
+++ b/caravel/utils/examples/edit.tcl
@@ -0,0 +1,26 @@
+# SPDX-FileCopyrightText: 2020 Efabless Corporation
+#
+# Licensed under the Apache License, Version 2.0 (the "License");
+# you may not use this file except in compliance with the License.
+# You may obtain a copy of the License at
+#
+#      http://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing, software
+# distributed under the License is distributed on an "AS IS" BASIS,
+# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+# See the License for the specific language governing permissions and
+# limitations under the License.
+# SPDX-License-Identifier: Apache-2.0
+
+drc off
+puts "Small delay..."
+set macro_mags "digital_pll.mag lvlshiftdown.mag striVe2_soc.mag striVe_clkrst.mag striVe_spi.mag"
+
+gds readonly yes
+gds rescale no
+gds read ../gds/sram_1rw1r_32_256_8_sky130.gds
+lef read ../lef/sram.abs.lef
+foreach ff $macro_mags { drc off; load $ff -dereference; after 1000; select top cell; property LEFview TRUE }
+load striVe2 -dereference
+select top cell
diff --git a/caravel/utils/examples/ext-gds.sh b/caravel/utils/examples/ext-gds.sh
new file mode 100644
index 0000000..c3efd7e
--- /dev/null
+++ b/caravel/utils/examples/ext-gds.sh
@@ -0,0 +1,43 @@
+#!/bin/bash
+# SPDX-FileCopyrightText: 2020 Efabless Corporation
+#
+# Licensed under the Apache License, Version 2.0 (the "License");
+# you may not use this file except in compliance with the License.
+# You may obtain a copy of the License at
+#
+#      http://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing, software
+# distributed under the License is distributed on an "AS IS" BASIS,
+# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+# See the License for the specific language governing permissions and
+# limitations under the License.
+# SPDX-License-Identifier: Apache-2.0
+
+
+export MAGTYPE=maglef ;
+export BASE=/home/mk/zooz/ ;
+export PDKPATH=$BASE/pdks/ef-skywater-s8/EFS8A ;
+
+magic -dnull -noconsole -rcfile $PDKPATH/libs.tech/magic/current/EFS8A.magicrc <<EOF
+gds polygon subcell true
+gds warning default
+gds read $1.gds
+load $1.mag
+save $1.mag
+writeall force
+select top cell
+extract style ngspice(si)
+extract
+ext2spice hierarchy on
+ext2spice format ngspice
+ext2spice cthresh infinite
+ext2spice rthresh infinite
+ext2spice renumber offS
+ext2spice scale off
+ext2spice blackbox on
+ext2spice subcircuit top auto
+ext2spice global off
+ext2spice $1.ext
+quit -noprompt
+EOF
diff --git a/caravel/utils/examples/ext-mag.sh b/caravel/utils/examples/ext-mag.sh
new file mode 100644
index 0000000..a62a831
--- /dev/null
+++ b/caravel/utils/examples/ext-mag.sh
@@ -0,0 +1,40 @@
+#!/bin/bash
+# SPDX-FileCopyrightText: 2020 Efabless Corporation
+#
+# Licensed under the Apache License, Version 2.0 (the "License");
+# you may not use this file except in compliance with the License.
+# You may obtain a copy of the License at
+#
+#      http://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing, software
+# distributed under the License is distributed on an "AS IS" BASIS,
+# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+# See the License for the specific language governing permissions and
+# limitations under the License.
+# SPDX-License-Identifier: Apache-2.0
+
+
+export MAGTYPE=mag ;
+export BASE=/home/mk/zooz/ ;
+export PDKPATH=$BASE/pdks/ef-skywater-s8/EFS8A ;
+
+magic -dnull -noconsole -rcfile $PDKPATH/libs.tech/magic/current/EFS8A.magicrc <<EOF
+load $1.mag
+save $1.mag
+writeall force
+select top cell
+extract style ngspice(si)
+extract
+ext2spice hierarchy on
+ext2spice format ngspice
+ext2spice cthresh infinite
+ext2spice rthresh infinite
+ext2spice renumber offS
+ext2spice scale off
+ext2spice blackbox on
+ext2spice subcircuit top auto
+ext2spice global off
+ext2spice $1.ext
+quit -noprompt
+EOF
diff --git a/caravel/utils/examples/ext.sh b/caravel/utils/examples/ext.sh
new file mode 100644
index 0000000..b414e8b
--- /dev/null
+++ b/caravel/utils/examples/ext.sh
@@ -0,0 +1,43 @@
+#!/bin/bash
+# SPDX-FileCopyrightText: 2020 Efabless Corporation
+#
+# Licensed under the Apache License, Version 2.0 (the "License");
+# you may not use this file except in compliance with the License.
+# You may obtain a copy of the License at
+#
+#      http://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing, software
+# distributed under the License is distributed on an "AS IS" BASIS,
+# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+# See the License for the specific language governing permissions and
+# limitations under the License.
+# SPDX-License-Identifier: Apache-2.0
+
+
+export MAGTYPE=maglef ;
+export BASE=/home/mk/zooz/ ;
+export PDKPATH=$BASE/pdks/ef-skywater-s8/EFS8A ;
+
+magic -dnull -noconsole -rcfile $PDKPATH/libs.tech/magic/current/EFS8A.magicrc <<EOF
+gds polygon subcell true
+gds warning default
+gds read $1.gds
+load $1.mag
+save $1.mag
+writeall force
+select top cell
+extract style ngspice(si)
+extract
+ext2spice hierarchy on
+ext2spice format ngspice
+ext2spice cthresh infinite
+ext2spice rthresh infinite
+ext2spice renumber off
+ext2spice scale off
+ext2spice blackbox on
+ext2spice subcircuit top auto
+ext2spice global off
+ext2spice $1.ext
+quit -noprompt
+EOF
diff --git a/caravel/utils/examples/extract.tcl b/caravel/utils/examples/extract.tcl
new file mode 100644
index 0000000..a38c9cb
--- /dev/null
+++ b/caravel/utils/examples/extract.tcl
@@ -0,0 +1,31 @@
+# SPDX-FileCopyrightText: 2020 Efabless Corporation
+#
+# Licensed under the Apache License, Version 2.0 (the "License");
+# you may not use this file except in compliance with the License.
+# You may obtain a copy of the License at
+#
+#      http://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing, software
+# distributed under the License is distributed on an "AS IS" BASIS,
+# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+# See the License for the specific language governing permissions and
+# limitations under the License.
+# SPDX-License-Identifier: Apache-2.0
+
+lef read $::env(PDKPATH)/libs.ref/techLEF/scs8hd/scs8hd_tech.lef
+set macro_mags "openram_tc_core.mag"
+
+# lef read ../lef/sram_1rw1r_32_256_8_sky130_lp1.lef
+
+foreach ff $macro_mags { drc off; after 500; load $ff -dereference; select top cell; property LEFview TRUE }
+
+load openram_tc_1kb -dereference
+
+select top cell
+extract do local
+extract
+ext2spice lvs
+ext2spice openram_tc_1kb.ext
+feedback save extract.tcl.log
+exit
diff --git a/caravel/utils/examples/lvs.sh b/caravel/utils/examples/lvs.sh
new file mode 100644
index 0000000..3a5043e
--- /dev/null
+++ b/caravel/utils/examples/lvs.sh
@@ -0,0 +1,22 @@
+#!/bin/sh
+# SPDX-FileCopyrightText: 2020 Efabless Corporation
+#
+# Licensed under the Apache License, Version 2.0 (the "License");
+# you may not use this file except in compliance with the License.
+# You may obtain a copy of the License at
+#
+#      http://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing, software
+# distributed under the License is distributed on an "AS IS" BASIS,
+# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+# See the License for the specific language governing permissions and
+# limitations under the License.
+# SPDX-License-Identifier: Apache-2.0
+
+/ef/apps/bin/netgen -noconsole << EOF
+readnet spice $1.spice
+readnet spice $1.sp
+lvs {$1.spice sram_2_16_sky130} {sram_2_16_sky130.sp sram_2_16_sky130} setup.tcl sram_2_16_sky130.lvs.report
+quit
+EOF
diff --git a/caravel/utils/examples/mag2gds.tcl b/caravel/utils/examples/mag2gds.tcl
new file mode 100644
index 0000000..8d7057d
--- /dev/null
+++ b/caravel/utils/examples/mag2gds.tcl
@@ -0,0 +1,33 @@
+# SPDX-FileCopyrightText: 2020 Efabless Corporation
+#
+# Licensed under the Apache License, Version 2.0 (the "License");
+# you may not use this file except in compliance with the License.
+# You may obtain a copy of the License at
+#
+#      http://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing, software
+# distributed under the License is distributed on an "AS IS" BASIS,
+# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+# See the License for the specific language governing permissions and
+# limitations under the License.
+# SPDX-License-Identifier: Apache-2.0
+
+# assumes an /ef tree or at least a symlink
+drc off
+gds readonly true
+gds rescale false
+set ::env(MAGTYPE) mag
+
+# gds read <hard macros read as-is.gds>
+gds read ../gds/sram_1rw1r_32_256_8_sky130_lp1.gds
+
+load sram_1rw1r_32_256_8_sky130 -dereference
+load openram_tc_core -dereference
+load openram_tc_1kb -dereference
+
+select top cell
+
+cif *hier write disable
+
+gds write openram_tc_1kb.gds
diff --git a/caravel/utils/examples/magic_drc.tcl b/caravel/utils/examples/magic_drc.tcl
new file mode 100644
index 0000000..554a4c6
--- /dev/null
+++ b/caravel/utils/examples/magic_drc.tcl
@@ -0,0 +1,71 @@
+# SPDX-FileCopyrightText: 2020 Efabless Corporation
+#
+# Licensed under the Apache License, Version 2.0 (the "License");
+# you may not use this file except in compliance with the License.
+# You may obtain a copy of the License at
+#
+#      http://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing, software
+# distributed under the License is distributed on an "AS IS" BASIS,
+# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+# See the License for the specific language governing permissions and
+# limitations under the License.
+# SPDX-License-Identifier: Apache-2.0
+set ::env(DESIGN_NAME) openram_tc_1kb
+drc off
+lef read ../lef/sram_1rw1r_32_256_8_sky130_lp1.lef
+load sram_1rw1r_32_256_8_sky130 -dereference
+load openram_tc_core -dereference
+load openram_tc_1kb -dereference
+
+drc style drc(full)
+drc euclidean on
+
+set fout [open drc.log w]
+set oscale [cif scale out]
+set cell_name $::env(DESIGN_NAME)
+magic::suspendall
+puts stdout "\[INFO\]: Loading $cell_name\n"
+flush stdout
+load $cell_name
+select top cell
+drc check
+set drcresult [drc listall why]
+
+
+set count 0
+puts $fout "$cell_name"
+puts $fout "----------------------------------------"
+foreach {errtype coordlist} $drcresult {
+	puts $fout $errtype
+	puts $fout "----------------------------------------"
+	foreach coord $coordlist {
+	    set bllx [expr {$oscale * [lindex $coord 0]}]
+	    set blly [expr {$oscale * [lindex $coord 1]}]
+	    set burx [expr {$oscale * [lindex $coord 2]}]
+	    set bury [expr {$oscale * [lindex $coord 3]}]
+	    set coords [format " %.3f %.3f %.3f %.3f" $bllx $blly $burx $bury]
+	    puts $fout "$coords"
+	    set count [expr {$count + 1} ]
+	}
+	puts $fout "----------------------------------------"
+}
+
+puts $fout "\[INFO\]: COUNT: $count"
+puts $fout "\[INFO\]: Should be divided by 3 or 4"
+
+puts $fout ""
+close $fout
+
+puts stdout "\[INFO\]: COUNT: $count"
+puts stdout "\[INFO\]: Should be divided by 3 or 4"
+puts stdout "\[INFO\]: DRC Checking DONE ($::env(DESIGN_NAME).drc)"
+flush stdout
+
+puts stdout "\[INFO\]: Saving mag view with DRC errors($::env(DESIGN_NAME).drc.mag)"
+# WARNING: changes the name of the cell; keep as last step
+save $::env(DESIGN_NAME).drc.mag
+puts stdout "\[INFO\]: Saved"
+
+exit 0
diff --git a/caravel/utils/examples/pfg.sh b/caravel/utils/examples/pfg.sh
new file mode 100644
index 0000000..9d8def1
--- /dev/null
+++ b/caravel/utils/examples/pfg.sh
@@ -0,0 +1,38 @@
+#!/bin/bash
+# SPDX-FileCopyrightText: 2020 Efabless Corporation
+#
+# Licensed under the Apache License, Version 2.0 (the "License");
+# you may not use this file except in compliance with the License.
+# You may obtain a copy of the License at
+#
+#      http://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing, software
+# distributed under the License is distributed on an "AS IS" BASIS,
+# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+# See the License for the specific language governing permissions and
+# limitations under the License.
+# SPDX-License-Identifier: Apache-2.0
+
+
+export PDKPATH=/home/mk/zooz/pdks/ef-skywater-s8/EFS8A
+export MAGTYPE=mag 
+
+padring \
+-L $PDKPATH/libs.ref/lef/s8iom0s8/s8iom0s8.lef \
+-L $PDKPATH/libs.ref/lef/s8iom0s8/power_pads_lib.lef \
+--def padframe.def padframe.cfg 
+
+magic -rcfile $PDKPATH/libs.tech/magic/current/EFS8A.magicrc -noc -dnull <<EOF
+def read padframe.def
+save padframe
+select top cell
+lef write padframe.lef
+gds write padframe.gds
+exit
+EOF
+
+
+
+
+
diff --git a/caravel/utils/examples/run_openram_tc_1kb.sh b/caravel/utils/examples/run_openram_tc_1kb.sh
new file mode 100644
index 0000000..408ce96
--- /dev/null
+++ b/caravel/utils/examples/run_openram_tc_1kb.sh
@@ -0,0 +1,23 @@
+#!/bin/bash
+# SPDX-FileCopyrightText: 2020 Efabless Corporation
+#
+# Licensed under the Apache License, Version 2.0 (the "License");
+# you may not use this file except in compliance with the License.
+# You may obtain a copy of the License at
+#
+#      http://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing, software
+# distributed under the License is distributed on an "AS IS" BASIS,
+# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+# See the License for the specific language governing permissions and
+# limitations under the License.
+# SPDX-License-Identifier: Apache-2.0
+
+#
+# Run netgen on striVe (top level)
+#
+
+NETGEN_SETUP=$PDK_ROOT/EFS8A/libs.tech/netgen/EFS8A_setup.tcl
+
+netgen -batch lvs "../spi/openram_tc_1kb.spice openram_tc_1kb" "../verilog/gl/openram_tc_1kb.synthesis.v openram_tc_1kb" ${NETGEN_SETUP} openram_tc_1kb_comp.out -json | tee openram_tc_1kb_comp_lvs.log
diff --git a/caravel/utils/examples/setup.tcl b/caravel/utils/examples/setup.tcl
new file mode 100644
index 0000000..193dd2f
--- /dev/null
+++ b/caravel/utils/examples/setup.tcl
@@ -0,0 +1,27 @@
+# SPDX-FileCopyrightText: 2020 Efabless Corporation
+#
+# Licensed under the Apache License, Version 2.0 (the "License");
+# you may not use this file except in compliance with the License.
+# You may obtain a copy of the License at
+#
+#      http://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing, software
+# distributed under the License is distributed on an "AS IS" BASIS,
+# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+# See the License for the specific language governing permissions and
+# limitations under the License.
+# SPDX-License-Identifier: Apache-2.0
+
+# We must flatten these because the ports are disconnected
+flatten class {-circuit1 dummy_cell_6t}
+flatten class {-circuit1 dummy_cell_1rw_1r}
+flatten class {-circuit1 dummy_cell_1w_1r}
+flatten class {-circuit1 bitcell_array_0}
+flatten class {-circuit1 pbitcell_0}
+flatten class {-circuit1 pbitcell_1}
+property {-circuit1 nshort} remove as ad ps pd
+property {-circuit1 pshort} remove as ad ps pd
+property {-circuit2 nshort} remove as ad ps pd
+property {-circuit2 pshort} remove as ad ps pd
+permute transistors
diff --git a/caravel/utils/examples/wrap.tcl b/caravel/utils/examples/wrap.tcl
new file mode 100644
index 0000000..fc2c87e
--- /dev/null
+++ b/caravel/utils/examples/wrap.tcl
@@ -0,0 +1,28 @@
+# SPDX-FileCopyrightText: 2020 Efabless Corporation
+#
+# Licensed under the Apache License, Version 2.0 (the "License");
+# you may not use this file except in compliance with the License.
+# You may obtain a copy of the License at
+#
+#      http://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing, software
+# distributed under the License is distributed on an "AS IS" BASIS,
+# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+# See the License for the specific language governing permissions and
+# limitations under the License.
+# SPDX-License-Identifier: Apache-2.0
+
+drc off
+gds readonly yes
+gds rescale no
+
+gds read ../macros/sram/riscv-sky130/sram_1rw1r_32_256_8_sky130.gds
+load sram_1rw1r_32_256_8_sky130
+
+select top cell
+property LEFview "TRUE"
+
+save pk_sram_1rw1r_32_256_8_sky130.mag
+
+# exec sed -i -E "/^.*GDS_END.*$/d" sram_1rw1r_32_256_8_sky130_original.mag
diff --git a/caravel/utils/examples/wrap2.tcl b/caravel/utils/examples/wrap2.tcl
new file mode 100644
index 0000000..db1db3c
--- /dev/null
+++ b/caravel/utils/examples/wrap2.tcl
@@ -0,0 +1,36 @@
+# SPDX-FileCopyrightText: 2020 Efabless Corporation
+#
+# Licensed under the Apache License, Version 2.0 (the "License");
+# you may not use this file except in compliance with the License.
+# You may obtain a copy of the License at
+#
+#      http://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing, software
+# distributed under the License is distributed on an "AS IS" BASIS,
+# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+# See the License for the specific language governing permissions and
+# limitations under the License.
+# SPDX-License-Identifier: Apache-2.0
+
+drc off
+gds readonly yes
+gds rescale no
+
+lef read ../lef/sram.abs.con.lef
+load sram_1rw1r_32_256_8_sky130
+
+select top cell
+expand
+property LEFview ""
+property LEFsymmetry ""
+property LEFclass ""
+
+box position 5um 5um
+getcell pk_sram_1rw1r_32_256_8_sky130
+
+save sram_1rw1r_32_256_8_sky130.mag
+
+gds write output.gds
+
+save
diff --git a/caravel/utils/examples/xor.drc b/caravel/utils/examples/xor.drc
new file mode 100644
index 0000000..14896ee
--- /dev/null
+++ b/caravel/utils/examples/xor.drc
@@ -0,0 +1,42 @@
+# A general XOR script
+# (https://www.klayout.de/forum/discussion/100/xor-vs-diff-tool)
+# This script uses KLayout's DRC language to implement a generic
+# XOR between two layouts. The name of the layouts is given
+# in $a and $b.
+
+# For layout-to-layout XOR with multiple cores, run this script with
+#   ./klayout -r xor.drc -rd thr=NUM_CORES -rd top_cell=TOP_CELL_NAME -rd a=a.gds -rd b=b.gds -rd ol=xor.gds -zz
+# (replace NUM_CORES by the desired number of cores to utilize
+
+# enable timing output
+verbose
+
+# set up input a
+a = source($a, $top_cell)
+
+# set up input b
+b = source($b, $top_cell)
+
+$o && report("XOR #{$a} vs. #{$b}", $o)
+$ol && target($ol, $co || "XOR")
+
+$thr && threads($thr) || threads(2)
+
+# collect all common layers
+layers = {}
+[ a.layout, b.layout ].each do |ly|
+  ly.layer_indices.each do |li|
+    i = ly.get_info(li)
+    layers[i.to_s] = i
+  end
+end
+
+# perform the XOR's
+layers.keys.sort.each do |l|
+  i = layers[l]
+  info("--- Running XOR for #{l} ---")
+  x = a.input(l) ^ b.input(l)
+  info("XOR differences: #{x.data.size}")
+  $o && x.output(l, "XOR results for layer #{l}")
+  $ol && x.output(i.layer, i.datatype, i.name)
+end
diff --git a/caravel/utils/examples/xor.sh b/caravel/utils/examples/xor.sh
new file mode 100644
index 0000000..6911062
--- /dev/null
+++ b/caravel/utils/examples/xor.sh
@@ -0,0 +1,22 @@
+#!/bin/sh
+# SPDX-FileCopyrightText: 2020 Efabless Corporation
+#
+# Licensed under the Apache License, Version 2.0 (the "License");
+# you may not use this file except in compliance with the License.
+# You may obtain a copy of the License at
+#
+#      http://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing, software
+# distributed under the License is distributed on an "AS IS" BASIS,
+# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+# See the License for the specific language governing permissions and
+# limitations under the License.
+# SPDX-License-Identifier: Apache-2.0
+
+
+: ${1?"Usage: $0 file1.gds file2.gds <top_level_module_name>"}
+: ${2?"Usage: $0 file1.gds file2.gds <top_level_module_name>"}
+: ${3?"Usage: $0 file1.gds file2.gds <top_level_module_name>"}
+
+klayout -r $(dirname $0)/xor.drc -rd top_cell=$3 -rd a=$1 -rd b=$2 -rd thr=$(nproc) -rd ol=xor.gds -zz
diff --git a/caravel/utils/ext-def-sky130A.sh b/caravel/utils/ext-def-sky130A.sh
new file mode 100644
index 0000000..51ec955
--- /dev/null
+++ b/caravel/utils/ext-def-sky130A.sh
@@ -0,0 +1,30 @@
+#!/bin/bash
+# SPDX-FileCopyrightText: 2020 Efabless Corporation
+#
+# Licensed under the Apache License, Version 2.0 (the "License");
+# you may not use this file except in compliance with the License.
+# You may obtain a copy of the License at
+#
+#      http://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing, software
+# distributed under the License is distributed on an "AS IS" BASIS,
+# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+# See the License for the specific language governing permissions and
+# limitations under the License.
+# SPDX-License-Identifier: Apache-2.0
+
+# To call: ./ext-def-sky130A.sh <target_path> <design_name> <pdk-root> [<output_path> default is <target_path>/results/]
+
+export TARGET_DIR=$1
+export DESIGN_NAME=$2
+export PDK_ROOT=$3
+export OUT_DIR=${4:-$TARGET_DIR/results/}
+export TCL_CALL_PATH=$(pwd)/core_scripts
+
+if ! [[ -d "$OUT_DIR" ]]
+then
+    mkdir $OUT_DIR
+fi
+
+bash ./core_scripts/magic-ext.sh $TARGET_DIR $DESIGN_NAME $PDK_ROOT "def" "sky130A" $OUT_DIR $TCL_CALL_PATH
diff --git a/caravel/utils/ext-gds-sky130A.sh b/caravel/utils/ext-gds-sky130A.sh
new file mode 100644
index 0000000..35071b8
--- /dev/null
+++ b/caravel/utils/ext-gds-sky130A.sh
@@ -0,0 +1,30 @@
+#!/bin/bash
+# SPDX-FileCopyrightText: 2020 Efabless Corporation
+#
+# Licensed under the Apache License, Version 2.0 (the "License");
+# you may not use this file except in compliance with the License.
+# You may obtain a copy of the License at
+#
+#      http://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing, software
+# distributed under the License is distributed on an "AS IS" BASIS,
+# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+# See the License for the specific language governing permissions and
+# limitations under the License.
+# SPDX-License-Identifier: Apache-2.0
+
+# To call: ./ext-gds-sky130A.sh <target_path> <design_name> <pdk-root> [<output_path> default is <target_path>/results/]
+
+export TARGET_DIR=$1
+export DESIGN_NAME=$2
+export PDK_ROOT=$3
+export OUT_DIR=${4:-$TARGET_DIR/results/}
+export TCL_CALL_PATH=$(pwd)/core_scripts
+
+if ! [[ -d "$OUT_DIR" ]]
+then
+    mkdir $OUT_DIR
+fi
+
+bash ./core_scripts/magic-ext.sh $TARGET_DIR $DESIGN_NAME $PDK_ROOT "gds" "sky130A" $OUT_DIR $TCL_CALL_PATH
diff --git a/caravel/utils/ext-mag-sky130A.sh b/caravel/utils/ext-mag-sky130A.sh
new file mode 100644
index 0000000..b57ec31
--- /dev/null
+++ b/caravel/utils/ext-mag-sky130A.sh
@@ -0,0 +1,30 @@
+#!/bin/bash
+# SPDX-FileCopyrightText: 2020 Efabless Corporation
+#
+# Licensed under the Apache License, Version 2.0 (the "License");
+# you may not use this file except in compliance with the License.
+# You may obtain a copy of the License at
+#
+#      http://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing, software
+# distributed under the License is distributed on an "AS IS" BASIS,
+# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+# See the License for the specific language governing permissions and
+# limitations under the License.
+# SPDX-License-Identifier: Apache-2.0
+
+# To call: ./ext-mag-sky130A.sh <target_path> <design_name> <pdk-root> [<output_path> default is <target_path>/results/]
+
+export TARGET_DIR=$1
+export DESIGN_NAME=$2
+export PDK_ROOT=$3
+export OUT_DIR=${4:-$TARGET_DIR/results/}
+export TCL_CALL_PATH=$(pwd)/core_scripts
+
+if ! [[ -d "$OUT_DIR" ]]
+then
+    mkdir $OUT_DIR
+fi
+
+bash ./core_scripts/magic-ext.sh $TARGET_DIR $DESIGN_NAME $PDK_ROOT "mag" "sky130A" $OUT_DIR $TCL_CALL_PATH
diff --git a/caravel/utils/gds2mag-mag.local.sh b/caravel/utils/gds2mag-mag.local.sh
new file mode 100644
index 0000000..110358b
--- /dev/null
+++ b/caravel/utils/gds2mag-mag.local.sh
@@ -0,0 +1,37 @@
+#!/bin/sh
+# SPDX-FileCopyrightText: 2020 Efabless Corporation
+#
+# Licensed under the Apache License, Version 2.0 (the "License");
+# you may not use this file except in compliance with the License.
+# You may obtain a copy of the License at
+#
+#      http://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing, software
+# distributed under the License is distributed on an "AS IS" BASIS,
+# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+# See the License for the specific language governing permissions and
+# limitations under the License.
+# SPDX-License-Identifier: Apache-2.0
+
+export PDK_ROOT=~/foss/pdks/open_pdks/sky130;
+export MAGTYPE=mag ; 
+export PDKPATH=$PDK_ROOT/sky130A ;
+export MAGIC=magic
+
+
+$MAGIC  -dnull -noconsole << EOF
+#------------------------------------------------------
+drc off
+#---------------------------------gds polygon subcell true
+gds warning default
+gds readonly true
+gds rescale false
+#---------------------------------tech unlock *
+gds read $1
+load ${1%.gds}
+#---------------------------------readspice ${1%.gds}.sp
+cellname delete "(UNNAMED)"
+save ${1%.gds}.mag
+quit -noprompt
+EOF
diff --git a/caravel/utils/gds2mag-mag.sh b/caravel/utils/gds2mag-mag.sh
new file mode 100644
index 0000000..d53b156
--- /dev/null
+++ b/caravel/utils/gds2mag-mag.sh
@@ -0,0 +1,37 @@
+#!/bin/sh
+# SPDX-FileCopyrightText: 2020 Efabless Corporation
+#
+# Licensed under the Apache License, Version 2.0 (the "License");
+# you may not use this file except in compliance with the License.
+# You may obtain a copy of the License at
+#
+#      http://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing, software
+# distributed under the License is distributed on an "AS IS" BASIS,
+# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+# See the License for the specific language governing permissions and
+# limitations under the License.
+# SPDX-License-Identifier: Apache-2.0
+
+export PDK_ROOT=~/foss/pdks/open_pdks/sky130;
+export MAGTYPE=mag ; 
+export PDKPATH=$PDK_ROOT/sky130A ;
+export MAGIC=magic
+
+
+$MAGIC -rcfile $PDKPATH/libs.tech/magic/current/sky130A.magicrc -dnull -noconsole << EOF
+#------------------------------------------------------
+drc off
+#---------------------------------gds polygon subcell true
+gds warning default
+gds readonly true
+gds rescale false
+#---------------------------------tech unlock *
+gds read $1
+load ${1%.gds}
+#---------------------------------readspice ${1%.gds}.sp
+cellname delete "(UNNAMED)"
+save ${1%.gds}.mag
+quit -noprompt
+EOF
diff --git a/caravel/utils/lef2maglef.sh b/caravel/utils/lef2maglef.sh
new file mode 100644
index 0000000..455c4a6
--- /dev/null
+++ b/caravel/utils/lef2maglef.sh
@@ -0,0 +1,60 @@
+#!/bin/bash
+# SPDX-FileCopyrightText: 2020 Efabless Corporation
+#
+# Licensed under the Apache License, Version 2.0 (the "License");
+# you may not use this file except in compliance with the License.
+# You may obtain a copy of the License at
+#
+#      http://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing, software
+# distributed under the License is distributed on an "AS IS" BASIS,
+# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+# See the License for the specific language governing permissions and
+# limitations under the License.
+# SPDX-License-Identifier: Apache-2.0
+
+
+export PDK_ROOT=~/foss/pdks/open_pdks/sky130;
+export MAGTYPE=mag ; 
+export PDKPATH=$PDK_ROOT/sky130A ;
+export MAGIC=magic
+
+
+$MAGIC -rcfile $PDKPATH/libs.tech/magic/current/sky130A.magicrc -dnull -noconsole << EOX 
+drc off
+lef read $1.lef
+load $1
+save $1.lef.mag
+#writeall force $1.lef.mag
+
+		# copy GDS properties from the MAG view into the MAGLEF view
+		set gds_properties [list]
+		set fp [open $1.mag r]
+			set mag_lines [split [read \$fp] "\n"]
+			foreach line \$mag_lines {
+				if { [string first "string GDS_" \$line] != -1 } {
+					lappend gds_properties \$line
+				}
+			}
+		close \$fp
+		set fp [open $1.lef.mag r]
+			set mag_lines [split [read \$fp] "\n"]
+			set new_mag_lines [list]
+			foreach line \$mag_lines {
+				if { [string first "<< end >>" \$line] != -1 } {
+					lappend new_mag_lines [join \$gds_properties "\n"]
+				}
+				lappend new_mag_lines \$line
+			}
+		close \$fp
+		set fp [open $1.lef.mag w]
+			puts \$fp [join \$new_mag_lines "\n"]
+		close \$fp
+
+
+quit
+EOX
+
+mv -f $1.lef.mag ../maglef/$1.mag
+rm -f $1.lef
diff --git a/caravel/utils/mag2maglef-mag.sh b/caravel/utils/mag2maglef-mag.sh
new file mode 100644
index 0000000..2934887
--- /dev/null
+++ b/caravel/utils/mag2maglef-mag.sh
@@ -0,0 +1,68 @@
+#!/bin/bash
+# SPDX-FileCopyrightText: 2020 Efabless Corporation
+#
+# Licensed under the Apache License, Version 2.0 (the "License");
+# you may not use this file except in compliance with the License.
+# You may obtain a copy of the License at
+#
+#      http://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing, software
+# distributed under the License is distributed on an "AS IS" BASIS,
+# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+# See the License for the specific language governing permissions and
+# limitations under the License.
+# SPDX-License-Identifier: Apache-2.0
+
+
+export PDK_ROOT=~/foss/pdks/open_pdks/sky130;
+export MAGTYPE=mag ; 
+export PDKPATH=$PDK_ROOT/sky130A ;
+export MAGIC=magic
+
+$MAGIC -rcfile $PDKPATH/libs.tech/magic/current/sky130A.magicrc -dnull -noconsole  <<EOF
+drc off
+load $1.mag
+select top cell
+expand
+lef write $1.lef -hide 
+quit -noprompt
+EOF
+
+$MAGIC -rcfile $PDKPATH/libs.tech/magic/current/sky130A.magicrc -dnull -noconsole << EOX 
+drc off
+lef read $1.lef
+load $1
+save $1.lef.mag
+#writeall force $1.lef.mag
+
+		# copy GDS properties from the MAG view into the MAGLEF view
+		set gds_properties [list]
+		set fp [open $1.mag r]
+			set mag_lines [split [read \$fp] "\n"]
+			foreach line \$mag_lines {
+				if { [string first "string GDS_" \$line] != -1 } {
+					lappend gds_properties \$line
+				}
+			}
+		close \$fp
+		set fp [open $1.lef.mag r]
+			set mag_lines [split [read \$fp] "\n"]
+			set new_mag_lines [list]
+			foreach line \$mag_lines {
+				if { [string first "<< end >>" \$line] != -1 } {
+					lappend new_mag_lines [join \$gds_properties "\n"]
+				}
+				lappend new_mag_lines \$line
+			}
+		close \$fp
+		set fp [open $1.lef.mag w]
+			puts \$fp [join \$new_mag_lines "\n"]
+		close \$fp
+
+
+quit
+EOX
+
+mv -f $1.lef.mag ../maglef/$1.mag
+rm -f $1.lef
diff --git a/caravel/utils/mag2maglef-maglef.localrc.sh b/caravel/utils/mag2maglef-maglef.localrc.sh
new file mode 100644
index 0000000..f167252
--- /dev/null
+++ b/caravel/utils/mag2maglef-maglef.localrc.sh
@@ -0,0 +1,68 @@
+#!/bin/bash
+# SPDX-FileCopyrightText: 2020 Efabless Corporation
+#
+# Licensed under the Apache License, Version 2.0 (the "License");
+# you may not use this file except in compliance with the License.
+# You may obtain a copy of the License at
+#
+#      http://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing, software
+# distributed under the License is distributed on an "AS IS" BASIS,
+# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+# See the License for the specific language governing permissions and
+# limitations under the License.
+# SPDX-License-Identifier: Apache-2.0
+
+
+export PDK_ROOT=~/foss/pdks/open_pdks/sky130;
+export MAGTYPE=maglef ; 
+export PDKPATH=$PDK_ROOT/sky130A ;
+export MAGIC=magic
+
+$MAGIC -dnull -noconsole  <<EOF
+drc off
+load $1.mag
+select top cell
+expand
+lef write $1.lef -hide
+quit -noprompt
+EOF
+
+$MAGIC -dnull -noconsole << EOX 
+drc off
+lef read $1.lef
+load $1
+save $1.lef.mag
+#writeall force $1.lef.mag
+
+		# copy GDS properties from the MAG view into the MAGLEF view
+		set gds_properties [list]
+		set fp [open $1.mag r]
+			set mag_lines [split [read \$fp] "\n"]
+			foreach line \$mag_lines {
+				if { [string first "string GDS_" \$line] != -1 } {
+					lappend gds_properties \$line
+				}
+			}
+		close \$fp
+		set fp [open $1.lef.mag r]
+			set mag_lines [split [read \$fp] "\n"]
+			set new_mag_lines [list]
+			foreach line \$mag_lines {
+				if { [string first "<< end >>" \$line] != -1 } {
+					lappend new_mag_lines [join \$gds_properties "\n"]
+				}
+				lappend new_mag_lines \$line
+			}
+		close \$fp
+		set fp [open $1.lef.mag w]
+			puts \$fp [join \$new_mag_lines "\n"]
+		close \$fp
+
+
+quit
+EOX
+
+mv -f $1.lef.mag ../maglef/$1.mag
+rm -f $1.lef
diff --git a/caravel/utils/mag2maglef-maglef.sh b/caravel/utils/mag2maglef-maglef.sh
new file mode 100644
index 0000000..e70fbd3
--- /dev/null
+++ b/caravel/utils/mag2maglef-maglef.sh
@@ -0,0 +1,68 @@
+#!/bin/bash
+# SPDX-FileCopyrightText: 2020 Efabless Corporation
+#
+# Licensed under the Apache License, Version 2.0 (the "License");
+# you may not use this file except in compliance with the License.
+# You may obtain a copy of the License at
+#
+#      http://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing, software
+# distributed under the License is distributed on an "AS IS" BASIS,
+# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+# See the License for the specific language governing permissions and
+# limitations under the License.
+# SPDX-License-Identifier: Apache-2.0
+
+
+export PDK_ROOT=~/foss/pdks/open_pdks/sky130;
+export MAGTYPE=maglef ; 
+export PDKPATH=$PDK_ROOT/sky130A ;
+export MAGIC=magic
+
+$MAGIC -rcfile $PDKPATH/libs.tech/magic/current/sky130A.magicrc -dnull -noconsole  <<EOF
+drc off
+load $1.mag
+select top cell
+expand
+lef write $1.lef 
+quit -noprompt
+EOF
+
+$MAGIC -rcfile $PDKPATH/libs.tech/magic/current/sky130A.magicrc -dnull -noconsole << EOX 
+drc off
+lef read $1.lef
+load $1
+save $1.lef.mag
+#writeall force $1.lef.mag
+
+		# copy GDS properties from the MAG view into the MAGLEF view
+		set gds_properties [list]
+		set fp [open $1.mag r]
+			set mag_lines [split [read \$fp] "\n"]
+			foreach line \$mag_lines {
+				if { [string first "string GDS_" \$line] != -1 } {
+					lappend gds_properties \$line
+				}
+			}
+		close \$fp
+		set fp [open $1.lef.mag r]
+			set mag_lines [split [read \$fp] "\n"]
+			set new_mag_lines [list]
+			foreach line \$mag_lines {
+				if { [string first "<< end >>" \$line] != -1 } {
+					lappend new_mag_lines [join \$gds_properties "\n"]
+				}
+				lappend new_mag_lines \$line
+			}
+		close \$fp
+		set fp [open $1.lef.mag w]
+			puts \$fp [join \$new_mag_lines "\n"]
+		close \$fp
+
+
+quit
+EOX
+
+mv -f $1.lef.mag ../maglef/$1.mag
+rm -f $1.lef
diff --git a/caravel/utils/magicDrc b/caravel/utils/magicDrc
new file mode 100644
index 0000000..fa6f783
--- /dev/null
+++ b/caravel/utils/magicDrc
@@ -0,0 +1,888 @@
+#!/bin/bash
+# SPDX-FileCopyrightText: 2015, 2020 Efabless Corporation
+#
+# Licensed under the Apache License, Version 2.0 (the "License");
+# you may not use this file except in compliance with the License.
+# You may obtain a copy of the License at
+#
+#      http://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing, software
+# distributed under the License is distributed on an "AS IS" BASIS,
+# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+# See the License for the specific language governing permissions and
+# limitations under the License.
+#
+# SPDX-License-Identifier: Apache-2.0
+# Copyright (C) 2015, 2020 efabless Corporation. All Rights Reserved.
+# filter out most options, so magic Natively sees/handles *only* -T <file>.
+# for-bash\
+  declare -a C ; declare -a N ; export _CE= _NE= _M0=           ;\
+  for i in "$@" ; do _M0="$_M0${_M0:+ }\"${i//\"/\\\"}\""; done ;\
+  while getopts "NFT:S:l:P:" o; do                      \
+    : echo got "optchar $o, with optarg $OPTARG" ;\
+    case "$o" in S)                               \
+      C+=(-${o} "$OPTARG")                       ;\
+       continue ; esac                           ;\
+    case "$o" in P)                               \
+      C+=(-${o} "$OPTARG")                       ;\
+       continue ; esac                           ;\
+    case "$o" in F|N)                             \
+      C+=(-${o})                                 ;\
+       continue ; esac                           ;\
+    case "$o" in l)                               \
+      C+=(-${o} "$OPTARG")                       ;\
+       continue ; esac                           ;\
+    case "$o" in T)                               \
+      N+=(-${o} "$OPTARG")                       ;\
+       continue ; esac                           ;\
+  done                ;\
+  shift $((OPTIND-1)) ;\
+  for i in "${C[@]}" ; do _CE="$_CE${_CE:+ }\"${i//\"/\\\"}\""; done ;\
+  for i in "${N[@]}" ; do _NE="$_NE${_NE:+ }\"${i//\"/\\\"}\""; done ;\
+  exec magic -dnull -noconsole "${N[@]}" <"$0"
+# for-magic:
+# magicDrc: run magic-DRC in batch on a .mag file, tabulate/pareto the error counts.
+#
+# magicDrc [-T <techfilePath>] [-S <drcStyleName>] [-P <N> ] [-l FILE_NAME] <magFileName>
+#  -T name specific techfile (def .tech extension), passed to magic itself only, overrides tech implied by magFileName
+#  -S if given, changes from techfile's default drc style (perhaps "drc(fast)") to named style, for example: -S "drc(full)"
+#  -l if given, enumerates EVERY individual error bbox to the FILE_NAME
+#  -N if given, do Not use -dereference option of load for topcell (not available in older magics)
+#  -F flatten top cell in-memory only, not saved (experimental)
+#  -P do crude drc performance measurement. At top-cell, do 'drc find' <N> times and report time per call.
+#   Stdout will log a pareto of error type by count regardless.
+#
+# <magFileName>: names a .mag file, the toplevel of the hier. to DRC/pareto
+#
+# Normal magic init. files are STILL sourced: ~/.magicrc and either $CWD/.magicrc or $CWD/magic_setup.
+# (This would NOT happen if -rcfile magic cmd-line option were used).
+#
+# WARNING: Before 8.1.70, *.mag on cmd-line that was only found in cell search path set by .magicrc inits,
+# would FAIL to determine the default tech-file.
+#
+# rb@ef 2015-06-30 author
+# rb 2020-03-11 embed some library functions, to standalone from efabless-opengalaxy env, test via magic-8.2.194
+#
+# magic itself outputs following usage message though -rcfile doesn't appear to work (in some versions):
+#   Usage:  magic [-g gPort] [-d devType] [-m monType] [-i tabletPort] [-D] [-F objFile saveFile]
+#   [-T technology] [-rcfile startupFile | -norcfile][-noconsole] [-nowindow] [-wrapper] [file]
+#
+set Prog "magicDrc"
+
+set argv  [eval "list $env(_M0)"] ;# orig. mix of native plus custom args, for logging all args to script
+
+proc usage {args} {
+    if {[llength $args] > 0} {
+	puts "ERROR: ${::Prog}: [join $args]"
+    }
+    puts {usage: [ -T <techfilePath> ] [-S <drcStyleName>] [-N] [-l FILE_NAME] <magFileName>}
+    puts "  -T name specific techfile, passed to magic itself only, overrides tech implied by magFileName"
+    puts "  -S if given, changes from techfile's default drc style (perhaps \"drc(fast)\") to named style, for example: -S \"drc(full)\""
+    puts "  -l if given, enumerates EVERY individual error bbox to the FILE_NAME"
+    puts "  -N if given, do not use -dereference option of load for topcell (not available in older magics)"
+    puts "  Stdout will log a pareto of error type by count regardless."
+    puts ""
+    puts "  Recommend to run in dir with a ./.magicrc (or ./magic_setup) to configure magic's"
+    puts "  cell search path, thru addpath statements, to locate all cells."
+}
+
+# optionally hardcode library proc-s (part of site-wide extensions - always available - in context of efabless/open-galaxy)
+# This is to make the script more standalone from efabless environment; but these capabilities should be native to magic.
+
+if {[info command scratchWritable] == {}} {
+    puts "${::Prog}: hardcoding library proc-s..."
+# Replacement for 'cellname list exists CELLNAME', to fix ambiguity for cell "0".
+# For cell "0" test for membership in 'cellname list allcells'.
+#
+# Instead of returning 0 for (non-existent) and cellname for exists,
+# returns regular 0/1 instead for non-existent/exists.
+#
+# Therefore NOT direct replacement for uses of 'cellname list exists CELL'.
+# Requires code changes.
+proc cellnameExists {cell} {
+    expr {$cell ne "0" && [cellname list exists $cell] eq $cell ||
+	  $cell eq "0" && [lsearch -exact [cellname list allcells] $cell] > -1}
+}
+
+#
+# scratchWritable [-cleanup] [cellname1 ...] --
+#
+# Turn readonly cells writable in-memory, via redirect to scratch dir.
+# No cellname args: default is to process just all non-writable cells.
+# Explicit cellname arguments: ARE scatchified EVEN if ALREADY writable.
+# Limitation: Explicit named cell created in-mem, never saved, won't scratchify.
+# If just -cleanup: default is to only do cleanup: don't scratchify
+# any cells.
+#
+# -cleanup: Last scratch-dir, if any, and contents are deleted first.
+# No restoring old filepath of cells, save after cleanup will fail.
+#
+# Caller strongly recommended to first do: 'select top cell; expand'
+# to force whole hier. of a topcell to be loaded from disk into memory.
+#
+# This proc does not force expand cells. Before expanded, cells cannot be
+# checked whether writable, and cannot have filepath changed.
+#
+# For batch DRC, for 'drc listall count', every cell in-memory must
+# appear writable.  This is the work-around (caller to 1st ensure
+# hier. is loaded): Reset filepath of readonly cells to a scratch dir,
+# make a dummy/empty .mag in scratch dir for each cell. Change cell's
+# writeable flag.
+#
+# Skipped cells:
+# In all cases, cells are skipped if
+#   'cellname filepath' matches ::scratchWritableDir (already scratchified),
+# This proc does NOT try and force expand; it presumes caller forced an expand
+# thus cells are skipped if:
+#   'cellname filepath' is "default" (can mean not expanded yet, or created never saved),
+#   'cellname filepath' is <CELLNAME>.mag, indicates failed expand (unbound).
+# Note: when filepath gives "default" or <CELLNAME>.mag, the writeable check not meaningful.
+#
+# How to scratchify all in-memory cells (still subject to internal skipping):
+#     scratchWritable {*}[cellname list allcells]
+#
+# TODO: use a combo of filepath & flags likely can detect created in-mem,
+# and could redirect those too scratch dir if named explicitly.
+#
+# Side-effects:
+#   Runs zero or one subprocess, '/bin/mktemp -d' to make a scratch dir.
+#   Redirects where newly modified cells would be saved, if they ever are saved.
+#   Make's a scratch dir that needs to be cleaned-up.
+#   Leaves empty *.mag files in that scratch dir.
+#
+# Uses/requires proc cellnameExists.
+#
+# Same scratch-dir is reused if called multiple times, until next -cleanup.
+#
+# return value: list of cells not processed (skipped) for reasons cited above.
+# Non-existent cells are also skipped but not included in the return list.
+#
+if {![info exists ::scratchWritableDir]} {set ::scratchWritableDir {}}
+if {![info exists ::scratchWritableVerb]} {set ::scratchWritableVerb 0}
+proc scratchWritable {args} {
+    # parse -cleanup option
+    set clean [expr {[lindex $args 0] eq {-cleanup}}]
+    if {$clean} {
+	set args [lrange $args 1 end]
+    }
+
+    # If explicit cells given: don't limit to processing just readOnly cells.
+    set onlyReadonly [expr {$args == {}}]
+
+    # only if no -cleanup, does empty cell list imply all cells
+    set allcell [cellname list allcells]
+    if {!$clean && $args == {}} {
+	set args $allcell
+    }
+
+    # do cleanup
+    if {$clean} {
+	if {$::scratchWritableDir != {} && [file isdir $::scratchWritableDir]} {
+	    set files [glob -dir $::scratchWritableDir -- {*.ext} {*.mag}]
+	    lappend files $::scratchWritableDir
+	    if {$::scratchWritableVerb} {
+		puts "scratchWritable: running, file delete $files"
+	    }
+	    eval {file delete} $files
+	    set ::scratchWritableDir {}
+	}
+    }
+
+    # Filter out non-existent or unbound cells.
+    # Optionally filter already writable cells.
+    #
+    # Unbounds result from placements of cells that now don't exist:
+    # fail to expand.  This proc does not try and force expand; it
+    # presumes a forced expand was already done by caller (if caller
+    # wished).
+    #
+    # Referenced/used cells are initially unexpanded, not yet even located
+    # located in the search path, 'cellname filepath' returns "default".
+    # If expand fails (not found in search path), then 'cellname filepath'
+    # returns <CELLNAME>.mag, if expand worked, the directory containing
+    # the cell.
+    #
+    # If cell was 'cellname create' made, but never saved also "default".
+    # Such a cell is writable. So filter "default" and <CELLNAME>.mag.
+    set skipped {}
+    set ercell1 {}
+    set docells {}
+    foreach cell $args {
+	# filter (without recording as skipped) non-existent cells.
+	if {![cellnameExists $cell]} { continue }
+
+	# filepath = "default": unexpanded (not loaded from disk),
+	# or created in-mem and never saved (is writable already
+	# though flags won't say so): skip both.
+	# TODO: use a combo of filepath & flags likely can detect created in-mem,
+	# and might be able to redirect them too to scratch dir if named explicitly.
+	set tmppath [cellname list filepath $cell]
+	if {$tmppath eq "default"} {
+	    lappend skipped $cell
+	    continue
+	}
+
+	# flags not meaningful, until expanded or expand attempted.
+	# After expand attempt (filepath != "default"), and flags
+	# can now be used to determine cell unbound: not available.
+	set flags   [cellname list flags    $cell]
+	if {[lsearch -exact $flags available] < 0} {
+	    lappend ercell1 $cell
+	    continue
+	}
+
+	if {$onlyReadonly &&
+	    [cellname list writeable $cell] eq "writeable"} {
+	    lappend skipped $cell
+	    continue
+	}
+	lappend docells $cell
+    }
+
+    if {$::scratchWritableVerb} {
+	puts "scratchWritable: skipped cells: $skipped"
+    }
+    
+    # don't make a scratch dir if no work to do
+    if {$docells == {}} {
+	if {$::scratchWritableVerb} {
+	    puts "scratchWritable: scratch-directed 0 cells"
+	}
+	return $skipped
+    }
+
+    # make a scratch dir if needed
+    if {$::scratchWritableDir == {}} {
+	if {[catch {set dir [string trimright [exec /bin/mktemp -d]]} msg]} {
+	    error "ERROR: scratchWritable, '/bin/mktemp -d' failed, $msg"
+	}
+	if {![file isdir $dir] || ![file writable $dir]} {
+	    error "ERROR: scratchWritable, mktemp gave $dir, not a writable dir"
+	}
+	set ::scratchWritableDir $dir
+    }
+
+    set ercell2 {}
+    set okcell {}
+    set madef 0
+    foreach cell $docells {
+	# Relocate if needed: filepath doesn't already point to the scratch dir).
+	# 'cellname list filepath <cellNm>' -> appears to omit .mag extension,
+	# but disk-file needs the .mag in the path.
+	set trgr [file join $::scratchWritableDir "$cell"]      ;# expected "lookup" path
+	set trgw [file join $::scratchWritableDir "$cell.mag"]  ;# true "write" disk path
+	set src [cellname list filepath $cell]
+	if {[cellname list filepath $cell] ne $trgr && [cellname list filepath $cell] ne $trgw} {
+
+	    # make empty .mag for the cell
+	    if {[catch {set outmag [open $trgw w]} msg]} {
+		lappend ercell2 $cell
+		continue
+	    }
+	    incr madef
+	    close $outmag
+
+	    # relocate cell to new file
+	    cellname list filepath $cell $::scratchWritableDir
+	}
+
+	# make cell writable
+	cellname list writeable $cell true
+	lappend okcell $cell
+    }
+
+    if {$::scratchWritableVerb} {
+	puts "scratchWritable: scratch-directed $madef cells"
+    }
+    if {$ercell1 != {} || $ercell2 != {}} {
+	set pre "ERROR: scratchWritable, "
+	set msg {}
+	if {$ercell1 != {}} {
+	    lappend msg "$pre unbound cell(s): $ercell1"
+	}
+	if {$ercell2 != {}} {
+	    lappend msg "$pre failed to make .mag for cell(s): $ercell2"
+	}
+	error [join $msg "\n"]
+    }
+    set skipped
+} ;# end proc scratchWritable
+}
+
+# without top-level proc around bulk of script, intermediate error statements don't abort script.
+proc main {argv} {
+
+# process name-value pair options, if any
+set nbrErr 0
+set ndx 0
+set max [llength $argv]
+set extTechOpt {} ;# -T ...
+set enumFilel  {} ;# -l ... enum output file
+set variant {}    ;# -S ... non-default drc style
+set flatten 0
+set perfN   0     ;# -P <N> do crude DRC perf. test
+set noderef 0     ;# -N disable dereference option of: 'load ... -dereference'
+
+while {$ndx < $max && [string match "-*" [lindex $argv $ndx]]} {
+    set opt [lindex $argv $ndx]
+    incr ndx
+    switch -exact -- $opt {
+	-T {
+	    if {$ndx == $max} {
+		usage "missing tech-file argument for -T option"
+		exit 1
+	    }
+	    set extTechOpt [lindex $argv $ndx]
+	    incr ndx
+	}
+	-S {
+	    if {$ndx == $max} {
+		usage "missing drcStyle argument for -S option"
+		exit 1
+	    }
+	    set variant [lindex $argv $ndx]
+	    incr ndx
+	}
+	-P {
+	    if {$ndx == $max} {
+		usage "missing count argument for -P option"
+		exit 1
+	    }
+	    set perfN [lindex $argv $ndx]
+	    incr ndx
+	}
+	-F {
+	    set flatten 1
+	}
+	-N {
+	    set noderef 1
+	}
+	-l {
+	    if {$ndx == $max} {
+		usage "missing outputFile argument for -l option"
+		exit 1
+	    }
+	    set enumFilel [lindex $argv $ndx]
+	    incr ndx
+	    if {[catch {set enumOut [open $enumFilel w]} msg]} {
+		error "ERROR: ${::Prog}: failed to open-for-write '$enumFilel' threw error, $msg"
+	    }
+	    puts "${::Prog}: enumerating each error bbox to: $enumFilel"
+	}
+	default {
+	    usage "unknown option: $opt"
+	    exit 1
+	}
+    }
+}
+
+if {$ndx == $max} {
+    usage "missing magFileName argument, the topcell"
+    exit 1
+}
+
+# get cmd-line topcell, minus dir-path; and minus extension IFF ext is .mag
+set topc [file tail [lindex $argv $ndx]] ; incr ndx
+if {[file extension $topc] eq ".mag"} {
+    set topc [file rootname $topc]
+}
+set topcStr $topc
+
+# abort if user supplies extra args.
+if {$ndx != $max} {
+    usage "extra/unspported arg past magFileName, '[lindex $argv $ndx]'"
+    exit 1
+}
+
+# load the techfile
+if {$extTechOpt != ""} {
+    if {![file readable $extTechOpt]} {
+	error "ERROR: ${::Prog}: tech-file \"$extTechOpt\" is not readable."
+    }
+
+    tech load $extTechOpt
+    
+    # Verify the cmd-line -T option (if any) is still the current 'tech filename'. If we didn't
+    # explicitly 'tech load' ourselves, the .magicrc or magic.setup might 'tech load' something else.
+    # The 'file join [pwd] ...' makes relative path absolute, but without resolving
+    # all symlinks (which 'file normalize' would do).
+    set techf2 [file join [pwd] [tech filename]]
+    set techf1 [file join [pwd]     $extTechOpt]
+    if {$techf1 != $techf2} {
+	error "ERROR: ${::Prog}: failed tech-load \"$techf1\" (tech-filename=\"$techf2\" not a match)"
+    }
+}
+
+# if mag-cell were passed natively on magic cmd-line, this is too late:
+if {$noderef} {
+    load $topc
+} else {
+    load $topc -dereference
+}
+
+# error checks: ensure (1st) cmd-line cellname now in-memory, and is now the current cell
+
+set topcells [cellname list top]
+# filter (UNNAMED)
+set topcells [lsearch -exact -not -all -inline $topcells "(UNNAMED)"]
+# puts "cellname-list-top is: $topcells"
+
+# could use [cellname list flags $topc] and ensure non-null result (list with available),
+# but if it fails (cell not found), it generates unwanted stdout.
+if {[lsearch -exact [cellname list allcells] $topc] < 0} {
+    error "ERROR: ${::Prog}: cmd-line topcell \"$topc\" not in magic's list of allcells."
+}
+
+if {[lsearch -exact $topcells $topc] < 0} {
+    puts "WARNING: ${::Prog}: cmd-line topcell \"$topc\" not in magic's list of topcells: $topcells"
+}
+
+# crude way even in batch to determine the "current" cell; perhaps not yet the "Edit" cell
+# WARNING, if topcell locked elsewhere or not writable, it can't become the "Edit" cell.
+set topcw [cellname list window]
+if {$topcw ne $topc} {
+    error "ERROR: ${::Prog}: cmd-line topcell, $topc, is not the current cell, 'cellname list window'=$topcw"
+}
+
+# for topcell, filepath==default doesn't change by expand,
+# indicates unknown cell created in-memory by magic's startup sequence.
+if {[cellnameExists         $topc] &&
+    [cellname list filepath $topc] eq "default"} {
+    puts "Search path for cells is \"[path search]\""
+    error "ERROR: ${::Prog}: cmd-line topcell, $topc, auto-created in-memory: not found in cell search path"
+}
+
+if {$flatten} {
+    # delete (UNNAMED) if any.
+    set trg "(UNNAMED)"
+    if {[cellnameExists $trg]} {cellname delete $trg}
+
+    # rename top cell to (UNNAMED)
+    cellname rename $topc $trg
+
+    # now Edit Cell contents are original top cell, but under name (UNNAMED)
+    # flatten Edit-Cell into original top cell name
+    puts "${::Prog}: flattening..."
+    flatten $topc
+
+    # load and edit new version of top cell. This is from in-memory, just making it current-cell.
+    # (So with or without -dereference is expected would have discernable effect by now;
+    # and since it's flattened there are no subcell instances either).
+    if {$noderef} {
+	load $topc
+    } else {
+	load $topc -dereference
+    }
+
+    # crude way even in batch to determine the "current" cell; perhaps not yet the "Edit" cell
+    # WARNING, if topcell locked elsewhere or not writable, it can't become the "Edit" cell.
+    set topcw [cellname list window]
+    if {$topcw ne $topc} {
+	error "ERROR: ${::Prog}: assertion failed, post-flatten, $topc, is not the current cell, 'cellname list window'=$topcw"
+    }
+
+    # should not be necessary:
+    select top cell
+    edit
+
+    # crude way even in batch to determine the "current" cell; perhaps not yet the "Edit" cell
+    # WARNING, if topcell locked elsewhere or not writable, it can't become the "Edit" cell.
+    set topcw [cellname list window]
+    if {$topcw ne $topc} {
+	error "ERROR: ${::Prog}: assertion-2 failed, post-flatten, $topc, is not the current cell, 'cellname list window'=$topcw"
+    }
+}
+
+# todo: Need a check for non-existent topcell (though magic reported not-found and auto-created it).
+# todo: We should locate fullpath to topcell on disk to record this in the log.
+#
+# WARNING, magic junkCell, or magic junkDir/junkCell (passing paths to cells that don't exist),
+# generate startup error messages (could not open cell), but magic creates the new cell in memory.
+# No simple way to detect this after the fact. Can walk the cell search path to verify it's on disk.
+# For the non-existent cell, magic also discards the dirpath from the cmd-line arg.
+# If it did exist at that path, magic opens it successfully, despite that dir not in search path.
+# A proper check for implicit create of non-existent cell should account for this effect too.
+
+# write a line with timestamp and all arguments to stdout (log)
+# (magic renames the TCL clock command)
+set clockp clock
+if {[info command $clockp] == {} && [info command orig_clock] != {}} {
+    set clockp orig_clock
+}
+set nowSec [$clockp seconds]
+set timestamp [$clockp format $nowSec -format "%Y-%m-%d.%T.%Z"]
+# Show quoted logged argv here so it's machine readable for replay purposes.
+puts "${::Prog}: timestamp: $timestamp, arguments: $::env(_M0)"
+
+puts "${::Prog}: running drc on topcell: $topcStr"
+puts "${::Prog}: tech-name: [tech name] -version: [tech version] -filename: [tech filename] -lambda [tech lambda]"
+
+# log the cell search path for this run. Emulates format output by plain "path" (but which prints more than one the cell search path).
+puts "Search path for cells is \"[path search]\""
+
+set res {}
+if {$variant != {}} {
+    if {[catch {set res [drc list style $variant]} msg]} {
+	puts "ERROR: ${::Prog}: but CONTINUING, 'drc style $variant' threw error, $msg"
+    }
+} else {
+    if {[catch {set res [drc list style]} msg]} {
+	puts "ERROR: ${::Prog}: but CONTINUING, 'drc list style' threw error, $msg"
+    }
+}
+if {$res != {}} {
+    puts "drc style reports:\n$res"
+}
+
+# just Manhattan is default, turn on euclidean, and log new mode
+drc euclidean on
+drc euclidean
+
+# 1st "select top cell": without it drc-list-count is blank, and error count reduced.
+# May be unnecessary in some cases.
+# WARNING: if topcell locked by another process, default box is NOT set to full top cell without this (as of 8.1.70 or earlier)
+select top cell
+# expand cell cells: scratchify step requires this up front else can't force all cells writable.
+expand
+
+# The expand triggered load of all subcells. Till then allcells may be incomplete.
+set allcells [cellname list allcells]
+# filter (UNNAMED)
+set allcells [lsearch -exact -not -all -inline $allcells "(UNNAMED)"]
+set nbrAllCells [llength $allcells]
+# puts "DEBUG: cellname-list-allcells are: $allcells"
+
+# TODO: do explicit separate unbound check here (don't rely on scratchWritable for this)
+
+# make allcells writable. Can error out:
+# if are unbounds, or couldn't make scratch dir or .mag files.
+set scratch [expr {!$flatten}]
+if {$scratch && [catch {scratchWritable} msg]} {
+    puts stderr "ERROR: ${::Prog}: aborting at scratchWritable due error(s):"
+    error $msg
+}
+
+# Erase all preexisting *.drtcl first. Else when cell transitions from
+# dirty in previous run (leaving *.drtcl), to clean, the old *.drtcl
+# remains.
+# TODO: only delete *.drtcl of cells in 'cellname list allcells'?
+# TODO: move this up, before scratchWritable?
+set files [glob -nocomplain -types {f} -- ./*.drtcl]
+if {$files != {}} {
+    # TODO: detect/report failure details better here?
+    puts "${::Prog}: deleting preexisting *.drtcl"
+    set msg {}
+    set delfail [catch {eval {file delete} $files} msg]
+    set files [glob -nocomplain -types {f} -- ./*.drtcl]
+    if {$delfail || $files != {}} {
+	puts "ERROR: ${::Prog}: failed to clean old ./*.drtcl files. $msg"
+	incr nbrErr
+    }
+}
+
+edit ;# Fails if topcell not writable, should not be not needed post scratchWritable
+
+set outScale [cif scale out]
+
+# "select top cell" and box [view bbox] should be equivalent in
+# placing a box around whole cell extent.
+# The box cmd ALSO prints lambda and micron user-friendly box data,
+# but it prints microns with not enough resolution,
+# (and no option to disable that flawed print out).
+#
+# todo: emulate box output in full, except for higher resolution,
+# here we only scale/print the overall bbox in microns.
+# select top cell       ;# paranoid, reset the box to data extents post-expand
+# set bbox [view bbox]
+# set bbs {}
+# foreach oord $bbox {
+#     lappend bbs [format "%.3f" [expr {$outScale * $oord}]]
+# }
+# puts "outScale: $outScale, view-bbox: $bbox"
+# puts "Root cell box2: ([lindex $bbs 0]  [lindex $bbs 1]), ([lindex $bbs 2]  [lindex $bbs 3])"
+
+# shouldn't need:
+# drc on
+
+# Want to use 'drc list count' to tell us which cells have errors, so we can
+# run 'drc listall why' on just those cells to enumerate details (which reruns
+# drc again unfortunately).
+
+# For accurate DRC (as of 8.1.70), specifically 'drc list count', need:
+# all-writable cells, then run: 'drc check' & 'drc catchup'.
+# Now we have all writable cells.
+set timeRepeat 1
+if {$perfN > 0} {
+    set timeRepeat $perfN
+}
+set timeres [time {
+    set drcCheckTime1 [time {drc check}]
+    set drcCheckTime2 [time {drc catchup}] } $timeRepeat]
+
+if {$perfN > 0} {
+    puts "perf: ${perfN}X 'drc check','drc catchup': $timeres"
+    puts "perf: last 'drc check' time: $drcCheckTime1"
+    puts "perf: last 'drc catchup' time: $drcCheckTime2"
+    drc statistics
+    drc rulestats
+}
+
+# todo: this 2nd select was in GDS version, test if needed in mag version:
+# 2nd select top cell needed else error count may be reduced (why? bbox does not change due to DRC)
+select top cell
+set outScale [cif scale out]
+set bbox [view bbox]
+set bbs {}
+foreach oord $bbox {
+    lappend bbs [format "%.3f" [expr {$outScale * $oord}]]
+}
+puts "outScale(ostyle=[cif list ostyle]): $outScale, view-bbox: $bbox"
+puts "Root cell box: ([lindex $bbs 0]  [lindex $bbs 1]), ([lindex $bbs 2]  [lindex $bbs 3])"
+# print several native bbox representations:
+box
+
+# listall vs list appear same as of 8.1.70 or earlier.
+# warning: celllist order is not stable, not repeatable; run to run on same data.
+# puts "DEBUG: (drc listall count total) is $drcListCountTot"
+set celllist [drc listall count]
+set celllist [lsearch -not -all -inline -index 0 -exact $celllist "(UNNAMED)"]
+# puts "DEBUG: (drc listall count) is [drc listall count]"
+set drcListCountTot [drc list count total]
+set nbrErrCells [llength $celllist]
+
+# TODO: major problem: 'drc listall why' repeated an every cell, will do subcells
+# multiple times, as many times as their depth in the hier.
+
+# canonicalize order of celllist, move topc to last (if present whatsoever).
+# force our own artificial entry for topc (zero errors) if not present (was clean)
+# puts "DEBUG: celllist before: $celllist"
+set topcPair [lsearch           -inline -index 0 -exact $celllist $topc]
+set celllist [lsearch -not -all -inline -index 0 -exact $celllist $topc]
+set celllist [lsort -index 0 -dictionary $celllist]
+if {$topcPair == {}} {
+    # puts "DEBUG: $topc clean, forcing celllist entry for it"
+    set topcPair [list $topc 0]
+}
+lappend celllist $topcPair
+# puts "DEBUG: celllist after: $celllist"
+# puts "DEBUG: adjusted celllist(drc list count) is $celllist"
+
+# loop over celllist
+set doFeedback 1 ;# TODO: add cmd-line option to control this
+
+# collect 'dry listall why' for the cells in 'cell list count' with non-zero errors
+# If 'drc listall why' does report zero (shouldn't since we're only processing cells
+# with non-zero counts), it unavoidably writes to console a No drc errors found message.
+# We don't want such polluting our list of per-cell pareto's, so don't risk running
+# drc why in-line, in-between per-cell paretos.
+array set cell2why [list $topc {}] ;# default at least empty topcell why list
+foreach pair $celllist {
+    if {[lindex $pair 1] < 1} {continue} ;# only happens for topcell if topcell clean
+    set acell [lindex $pair 0]
+
+    # TODO: magic needs a useful error checkable load command.
+    # The 'load' writes errors to console/stdout, but never throws an error,
+    # nor gives a useful return value. i.e. These catch never catch.
+    if {$noderef} {
+	if {[catch {set res [load $acell]} msg]} {
+	    puts "ERROR: ${::Prog}: 'load $acell' threw error, $msg"
+	    exit 1
+	}
+    } else {
+	if {[catch {set res [load $acell -dereference]} msg]} {
+	    puts "ERROR: ${::Prog}: 'load $acell -dereference' threw error, $msg"
+	    exit 1
+	}
+    }
+    select top cell ;# paranoid, that without it, drc's are reduced
+
+    # optionally do crude DRC perf. analysis here. Only for top-cell, only if -P <N> option given.
+    set timeRepeat 1
+    if {$perfN > 0 && $topc eq $acell} {
+	set timeRepeat $perfN
+    }
+    set timeres [time {set cell2why($acell) [drc listall why]} $timeRepeat]
+    if {$perfN > 0 && $topc eq $acell} {
+	puts "perf: ${::Prog}: for '$acell', ${perfN}X 'drc listall why': $timeres"
+    }
+}
+
+# done with all magic-specifics here. Shouldn't need scratch dir any longer.
+# If this prints something (generally does), don't want it after the pareto table.
+
+# clean/remove the tmp scratch dir and contents
+# TODO: all fatal errors need to call a cleanup proc that includes this before abort
+if {$scratch && [catch {scratchWritable -cleanup} msg]} {
+    puts "ERROR: ${::Prog}: 'scratchWritable -cleanup' threw error, $msg"
+    incr nbrErr
+}
+
+set gtotal 0
+set gcells 0
+foreach pair $celllist {
+    puts ""
+    set acell [lindex $pair 0]
+    if {![info exists cell2why($acell)]} {
+	puts "ERROR: ${::Prog}: cell: $acell, assertion failed, no drc-why list for 'drc list count' pair: $pair"
+	# exit 1
+	continue
+    }
+    set whys $cell2why($acell)
+
+    # enumerate errors under box, plain "drc why" only reports unique types, no quantities
+    # as-yet-undocumented "drc listall why" gives: {errStr1 {errBox1 ...} errStr2 {errBox1 ...} ... }
+    set pareto {}
+    set total 0
+    set enumTotal 0
+    set types 0
+    set typeDup 0
+    set dups 0
+
+    set fbOut {}
+    # file path for feedback, keep in CWD
+    if {$doFeedback && $fbOut == {}} {
+	set fbOut "./$acell.drtcl"
+	if {![file writable $fbOut] &&
+	    ([file exists $fbOut] || ![file writable [file dir $fbOut]])} {
+	    puts stderr "ERROR: ${::Prog}: feedback output not writable, $fbOut"
+	    incr nbrErr
+	    set fbOut {}
+	} elseif {[catch {set outfb [open $fbOut w]} msg]} {
+	    puts stderr "ERROR: ${::Prog}: failed to truncate previous feedback output, $fbOut : $msg"
+	    incr nbrErr
+	    set fbOut {}
+	}
+    }
+    foreach {str boxes} $whys {
+	# sort errors
+	set boxes [lsort -dictionary $boxes]
+
+	# for our pareto, gather data
+	set this [llength $boxes]
+	incr total $this
+	incr types
+	lappend pareto [list $this $str]
+
+	# for enumOut, emulate formatting of $CAD_ROOT/magic/tcl/drc.tcl, which is
+	# not tk pure: fails with complaint about winfo
+	# note: we walk these errors also in order to count/report stats on duplicates, even if not outputing enumerations
+	if {[info exists enumOut]} {
+	    if {$types == 1} {
+		puts $enumOut "[join $pair]\n----------------------------------------"
+	    }
+	    puts $enumOut "${str}\n----------------------------------------"
+	}
+	set lastq {}
+	set thisDup 0
+	foreach quad $boxes {
+	    set quadUM {}
+	    foreach coord $quad {
+		set valum [expr {$coord * $outScale}]
+		set valumf [format "%.3f" $valum]
+		lappend quadUM "${valumf}um"
+	    }
+	    set dup [expr {$quad == $lastq}]
+	    incr thisDup $dup
+	    set line $quadUM
+	    if {[info exists enumOut]} {
+		if {$dup} {
+		    puts $enumOut "[join $line] #dup"
+		} else {
+		    puts $enumOut [join $line]
+		}
+	    }
+	    if {$fbOut != {}} {
+		set line [join $quadUM]
+		regsub -all -- "(\[\[\"\$\\\\])" $str {\\\1} strdq
+		puts $outfb "[concat box $line]"                nonewline
+		puts $outfb " ; feedback add \"$strdq\" medium" nonewline
+		if {$dup} {
+		    puts $outfb " ;#dup"
+		} else {
+		    puts $outfb ""
+		}
+	    }
+
+	    incr enumTotal
+	    set lastq $quad
+	}
+	if {$thisDup} {
+	    incr typeDup
+	    incr dups $thisDup
+	}
+	if {[info exists enumOut]} {
+	    puts $enumOut "----------------------------------------\n"
+	}
+    }
+
+    if {$fbOut != {}} {
+	close $outfb
+	set outfb {}
+    }
+
+    set pareto [lsort -integer -decreasing -index 0 $pareto]
+    if {$total > 0} {
+	puts "--- #err|description, table for cell: $acell"
+    }
+    foreach pair $pareto {
+	puts "[format {%8d} [lindex $pair 0]] [lindex $pair 1]"
+    }
+    if {$typeDup} {
+	puts "[format {%8d} $dups] total duplicate error(s) among $typeDup error type(s), cell: $acell"
+    }
+    puts "[format {%8d} $total] total error(s) among $types error type(s), cell: $acell"
+    # add to grand-totals
+    incr gcells
+    incr gtotal $total
+
+    # always compare the total from the enum to the pareto as error check
+    if {$total != $enumTotal} {
+	puts "ERROR: ${::Prog}: cell: $acell, assertion failed, pareto vs enum count mismatch: $total != $enumTotal"
+	incr nbrErr
+    }
+}
+
+# TODO: in the summary echo also techfile-full-path and drc-style name?
+# grand totals
+puts "[format {%8d} $nbrErrCells] of $nbrAllCells cell(s) report error(s)"
+puts "[format {%8d} $gtotal] grand-total error(s) across $gcells cell(s)"
+
+# wish to compare the drc-list-count-total to the pareto total.
+# Per te 2014-08-27 : it is not an error.
+# if {$total != $drcListCountTot} {
+#   puts "info: ${::Prog}: drc-list-count-total vs drc-listall-why mismatch {drc list count total} gave $drcListCountTot, but {drc listall why} gave $total"
+# }
+
+if {[info exists enumOut]} {
+    close $enumOut
+}
+
+# set celllist4 [drc list count]
+# puts "DEBUG: drc list count0: $celllist0"
+# puts "DEBUG: drc list count1: $celllist1"
+# puts "DEBUG: drc list count2: $celllist2"
+# puts "DEBUG: drc list count3: $celllist3"
+# puts "DEBUG: native (drc list count) is $celllistn"
+# puts "DEBUG: drc list count4: $celllist4"
+
+# todo: implement super-pareto, ranked table of SUM of all DRC errs/counts from ALL cells.
+# (It still would not reflect as-if-flat hierarchical expansion due to repetition of instances).
+
+set nbrErr
+}
+
+# non-zero exit-status on errors, either if thrown by main, or counted and returned by main
+set nbrErr 0
+if {[catch {set nbrErr [main $argv]} msg]} {
+    puts stderr $msg
+    set nbrErr 1
+} elseif {$nbrErr > 0} {
+    puts "ERROR: ${::Prog}: script terminated with errors reported above."
+}
+exit $nbrErr
+
+# for emacs syntax-mode:
+# Local Variables:
+# mode:tcl
+# End:
diff --git a/caravel/utils/magicGdrc b/caravel/utils/magicGdrc
new file mode 100644
index 0000000..88280ee
--- /dev/null
+++ b/caravel/utils/magicGdrc
@@ -0,0 +1,911 @@
+#!/bin/sh
+# SPDX-FileCopyrightText: 2014, 2015, 2020 Efabless Corporation
+#
+# Licensed under the Apache License, Version 2.0 (the "License");
+# you may not use this file except in compliance with the License.
+# You may obtain a copy of the License at
+#
+#      http://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing, software
+# distributed under the License is distributed on an "AS IS" BASIS,
+# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+# See the License for the specific language governing permissions and
+# limitations under the License.
+#
+# SPDX-License-Identifier: Apache-2.0
+# Copyright (C) 2014, 2015, 2020 efabless Corporation. All Rights Reserved.
+# send a very-first -T FILE to magic's startup, hide all other args from magic-startup
+# for-bash\
+  export _M0= ;\
+  for i in "$@" ; do _M0="$_M0${_M0:+ }\"${i//\"/\\\"}\""; done ;\
+  case "$1" in -T) tch="$2"; shift; shift; _MARGS="$*" exec magic -dnull -noconsole -T "$tch" <"$0" ;; esac
+# hide next line from magic(tclsh):\
+_MARGS="$*" exec magic -dnull -noconsole <"$0"
+#
+# magicDRC: run magic-DRC in batch on a GDS file, tabulate/pareto the error counts.
+# 
+# rb@ef 2014-08-28 author
+# rb 2020-02-19 embed some library functions, to standalone from efabless-opengalaxy env, test via magic-8.2.188
+#
+# todo: support "-" as GDS file arg, to mean GDS from stdin
+#
+
+set ::Prog "magicGdrc"
+set argv  [eval "list $env(_M0)"] ;# orig. mix of native plus custom args, for logging all args to script
+# set argv [split $env(_MARGS)]   ;# (currently unused)
+
+proc usage {args} {
+    if {[llength $args] > 0} {
+	puts "ERROR: ${::Prog}: [join $args]"
+    }
+    puts {usage: [ -T techfilePath ] [-S <drcStyleName>]  [-I <cifIStyleName>] [-km FILE_NAME] [-l FILE_NAME] [-L FILE_NAME] gdsFileName [topCellName]}
+    puts "  -T if given, must be very first"
+    puts "  -S if given, changes from techfile's default/1st drc style (perhaps \"drc(fast)\") to named style, for example: -S \"drc(full)\""
+    puts "  -I if given, changes from techfile's default/1st cifinput style (perhaps \"vendorimport\" or \"import(exact)\") to named style, for example: -I \"import(magic)\""
+    puts "  -path-sub do 'gds path    subcell yes' (default:no). Make unique subcell for each path: cut #tiles cost of angles."
+    puts "  -poly-sub do 'gds polygon subcell yes' (default:no). Make unique subcell for each polygon: cut #tiles cost of angles."
+# gds polygon subcell [yes|no]
+    puts "  -pps  Short hand, equivalent to giving both: -path-sub -poly-sub"
+    puts ""
+    puts "  Error tabulation: By default (slowest, most detail): Report table of counts-by-errorString for all cells."
+    puts "  Stdout logs a pareto of error-type by count unless disabled for some/all cells by below; topcell last."
+    puts "  -tt Table of counts-by-errorString for ONLY topcell; and just lumped total error count per subcell."
+    puts "  -tc Just lumped error counts per cell including topcell (fastest, least detail)."
+    puts "  Cells NOT tabulating count-by-errorString can't appear in other output error files: feedback(*.drtcl), -l, -km."
+    puts "  For lumped error counts, overlapped error shapes from unique error-types are merged further reducing count."
+    puts ""
+    puts "  cell-type +--    (default)     --+--  option -tt      --+--   option -tc"
+    puts "    subcell | count-by-errorString |   lumped-error-count | lumped-error-count"
+    puts "    topcell | count-by-errorString | count-by-errorString | lumped-error-count"
+    puts ""
+    puts "  -km if given, write to FILE_NAME EVERY individual error bbox (MICRONS) in klayout Marker database(XML) format (suggest *.lyrdb)"
+    puts "  -l if given, enumerates EVERY individual error bbox (MICRONS) to FILE_NAME, emulates $::CAD_ROOT/magic/tcl/drc.tcl"
+    puts "  -L same as -l above, but outputs bbox-es in LAMBDA coordinates, not microns"
+    puts "  -nf  Do NOT write *.drtcl per-cell feedback files. Can be source-ed in magic and step thru: feedback find."
+    puts ""
+    puts "  NOTES: Without explicit tech-file option: the ./.magicrc or ./magic_setup and ~/.magicrc may load a default tech-file."
+    puts "  Therefore the tech-file used CAN depend on whether your CWD is ~/design/<CURRENT_DESIGN>/mag when running this script."
+    puts "  Since no *.mag are loaded by this script: the cell search path defined by any init files has no impact."
+    puts "  Since about 8.3.68, magic may generate error-type \"See error definition in the subcell\". There typically are"
+    puts "  redundancies of errors across the hierarchy anyway (but with tech-file err-strings), this seems another form."
+    puts ""
+    puts "example, just list all styles: by causing an error which provokes usage report:"
+    puts "    magicGdrc -T /ef/tech/XFAB/EFXH035B/libs.tech/magic/current/EFXH035B.tech"
+    puts "example, same but run in a ~/design/*/mag/ dir, so techfile set by ./.magicrc (else magic's builtin minimum.tech):"
+    puts "    magicGdrc"
+    puts "example, run GDS drc, explicit: tech, cif-istyle, drc-style:"
+    puts "    magicGdrc -T /ef/tech/SW/EFS8A/libs.tech/magic/current/EFS8A.tech -I vendorimport -S 'drc(full)' /tmp/mytop.gds mytopcell"
+    puts "example, run GDS drc, default tech & styles, write klayout marker database, no per-cell *.drtcl feedback files:"
+    puts "    magicGdrc -km /tmp/mytop.lyrdb -nf /tmp/mytop.gds mytopcell"
+    puts "example, same but make subcells for paths & polygons"
+    puts "    magicGdrc -km /tmp/mytop.lyrdb -nf -pps /tmp/mytop.gds mytopcell"
+    puts "example, run GDS drc, no feedback (*.drtcl), only lumped/merged err-count for all cells"
+    puts "    magicGdrc -tc /tmp/mytop.gds mytopcell"
+    puts "example, run GDS drc, no feedback (*.drtcl), lumped/merged err-count for subcells, detail errors for topcell"
+    puts "    magicGdrc -nf -tt /tmp/mytop.gds mytopcell"
+    puts ""
+
+    reportTechFile
+    reportAllStyles
+    puts ""
+
+    if {[llength $args] > 0} {
+	puts "ERROR: ${::Prog}: [join $args]"
+    }
+}
+proc gdsChk {file} {
+    foreach suffix {"" ".gds" ".gds2" ".strm"} {
+	if {[file readable "${file}${suffix}"]} {return 1}
+    }
+    puts "ERROR: ${::Prog}: Cannot open (as-is or with .gds, .gds2, or .strm) to read GDS-II stream from: $file"
+    exit 1
+}
+
+proc reportTechFile {} {
+    puts "${::Prog}: tech-name: [tech name] -version: [tech version] -filename: [tech filename] -lambda [tech lambda]"
+}
+
+# query currently loaded tech-file for styles the user might need for -I -S options
+# Suggest a bad tech-file if none are found or errors thrown.
+# Used after finding error in -I -S options, and probably should add it to the usage.
+proc reportAllStyles {} {
+    set errs {}
+    if {[catch {set allstyle [cif listall istyle]} msg]} {
+	lappend errs "ERROR: ${::Prog}: bad tech-file? failed to 'cif listall istyle', $msg"
+    } elseif {$allstyle == {}} {
+	lappend errs "ERROR: ${::Prog}: bad tech-file? no cifinput styles found by 'cif listall istyle'"
+    } else {
+	puts "info: ${::Prog}: cifinput styles available: $allstyle"
+    }
+    if {[catch {set allstyle [drc listall style]} msg]} {
+	lappend errs "ERROR: ${::Prog}: bad tech-file? failed to 'drc listall style', $msg"
+    } elseif {$allstyle == {}} {
+	lappend errs "ERROR: ${::Prog}: bad tech-file? no drc styles found by 'drc listall style'"
+    } else {
+	puts "info: ${::Prog}: drc styles available: $allstyle"
+    }
+    if {$errs != {}} {
+
+    }
+    return [llength $errs]
+}
+
+# optionally hardcode library proc-s (part of site-wide extensions - always available - in context of efabless/open-galaxy)
+# This is to make the script more standalone from efabless environment; but these capabilities should be native to magic.
+
+if {[info command unbounds] == {}} {
+    puts "${::Prog}: hardcoding library proc-s..."
+# Replacement for 'cellname list exists CELLNAME', to fix ambiguity for cell "0".
+# For cell "0" test for membership in 'cellname list allcells'.
+#
+# Instead of returning 0 for (non-existent) and cellname for exists,
+# returns regular 0/1 instead for non-existent/exists.
+#
+# Therefore NOT direct replacement for uses of 'cellname list exists CELL'.
+# Requires code changes.
+proc cellnameExists {cell} {
+    expr {$cell ne "0" && [cellname list exists $cell] eq $cell ||
+	  $cell eq "0" && [lsearch -exact [cellname list allcells] $cell] > -1}
+}
+
+# Walk allcells to get/return list of cellNames that are unbound.
+# Only use this after: 'select top cell; expand' to expand whole hierarchy.
+#
+# foreach CELL in 'cellname list allcells':
+#   if flags says available : it's Bound, goto next cell.
+#   if filepath is "default", try to expand the cell.
+#   if still "default"**: cell made by "cellname create", never saved, goto next.
+#   if filepath is CELL.mag, check for "available" flags, if none: Unbound.
+#   else cell is bound.
+#   **: should never get there
+proc unbounds {} {
+    set allcells [cellname list allcells]
+    # filter (UNNAMED)
+    set allcells [lsearch -exact -not -all -inline $allcells "(UNNAMED)"]
+    # set nbrAllCells [llength $allcells]
+    set ercell {}
+    foreach cell $allcells {
+	# filter (without recording as skipped) non-existent cells.
+	if {![cellnameExists $cell]} { continue }
+
+	# filepath = "default": unexpanded (not loaded from disk),
+	# or created in-mem and never saved (is writable already
+	# though flags won't say so): skip both.
+	# TODO: use a combo of filepath & flags likely can detect created in-mem
+	set tmppath [cellname list filepath $cell]
+	if {$tmppath eq "default"} {
+	    lappend skipped $cell
+	    continue
+	}
+
+	# flags not meaningful, until expanded or expand attempted.
+	# After expand attempt (filepath != "default"), and flags
+	# can now be used to determine cell unbound: not available.
+	set flags   [cellname list flags    $cell]
+	if {[lsearch -exact $flags available] < 0} {
+	    lappend ercell $cell
+	    continue
+	}
+    }
+    set ercell ;# return list of unbound cells, if any
+}
+}
+
+# without top-level proc around bulk of script, intermediate error statements don't abort script.
+proc main {argv} {
+
+set mlen [llength $argv]
+
+# process name-value pair options, if any
+set nbrErr 0
+set ndx 0
+set max [llength $argv]
+set extTechOpt {} ;# -T ... but not used here
+set enumFilel  {} ;# -l ... enum output file
+set enumFileL  {} ;# -L ... enum output file
+set enumFileKm {} ;# -km ... enum output file
+set variant {}    ;# -S ... non-default drc style
+set istyle  {}    ;# -I ... non-default cifinput style
+set doFeedback 1  ;# -nf sets to 0: Do not write *.drtcl per-cell feedback files.
+set pathSub 0     ;# -path-sub ... do 'gds path    subcell yes'
+set polySub 0     ;# -poly-sub ... do 'gds polygon subcell yes'
+set subcellTab 1  ;# -tt, -tc both turn OFF subcell count-by-error report
+set topcellTab 1  ;#      -tc     turns OFF topcell count-by-error report
+set flatten 0
+while {$ndx < $max && [string match "-*" [lindex $argv $ndx]]} {
+    set opt [lindex $argv $ndx]
+    incr ndx
+    switch -exact -- $opt {
+	-T {
+	    if {$ndx != 1} {
+		usage "-T option must very 1st (here was #$ndx)"
+		exit 1
+	    }
+	    if {$ndx == $max} {
+		usage "missing tech-file argument for -T option"
+		exit 1
+	    }
+	    set extTechOpt [lindex $argv $ndx] ;# unused
+	    incr ndx
+	}
+	-S {
+	    if {$ndx == $max} {
+		usage "missing drcStyle argument for -S option"
+		exit 1
+	    }
+	    set variant [lindex $argv $ndx]
+	    incr ndx
+	}
+	-I {
+	    if {$ndx == $max} {
+		usage "missing cifinput-style argument for -I option"
+		exit 1
+	    }
+	    set istyle [lindex $argv $ndx]
+	    incr ndx
+	}
+	-F        { set flatten     1}
+	-nf       { set doFeedback 0 }
+	-path-sub { set pathSub     1}
+	-poly-sub { set polySub     1}
+	-pps      { set pathSub     1; set polySub     1}
+	-tt       { set subcellTab 0 ; set topcellTab  1}
+	-tc       { set subcellTab 0 ; set topcellTab 0 }
+	-km {
+	    if {$ndx == $max} {
+		usage "missing outputFile argument for -km option"
+		exit 1
+	    }
+	    set enumFileKm [lindex $argv $ndx]
+	    incr ndx
+	}
+	-l {
+	    if {$ndx == $max} {
+		usage "missing outputFile argument for -l option"
+		exit 1
+	    }
+	    set enumFilel [lindex $argv $ndx]
+	    incr ndx
+	    if {[catch {set enumOut [open $enumFilel w]} msg]} {
+		error "ERROR: ${::Prog}: failed to open-for-write '$enumFilel' threw error, $msg"
+	    }
+	    puts "${::Prog}: enumerating each error bbox to: $enumFilel"
+	}
+	-L {
+	    if {$ndx == $max} {
+		usage "missing outputFile argument for -L option"
+		exit 1
+	    }
+	    set enumFileL [lindex $argv $ndx]
+	    incr ndx
+	    if {[catch {set enumOutL [open $enumFileL w]} msg]} {
+		error "ERROR: ${::Prog}: failed to open-for-write '$enumFileL' threw error, $msg"
+	    }
+	    puts "${::Prog}: enumerating each error bbox to: $enumFileL"
+	}
+	default {
+	    usage "unknown option: $opt"
+	    exit 1
+	}
+    }
+}
+
+if {$ndx == $max} {
+    usage {Insufficient number of arguments, need gdsFileName [topCellName]}
+    exit 1
+}
+
+set gdsf [lindex $argv $ndx] ; incr ndx
+set topc {}
+set topcStr "(AUTO)"
+if {$ndx < $max} {
+    set topc [lindex $argv $ndx] ; incr ndx
+    set topcStr $topc
+}
+# error if extra options (not understood, something is wrong):
+if {$ndx < $max} {
+    error "ERROR: ${::Prog}: after gdsFile=\"$gdsf\", topcell=\"$topc\" found unsupported extra arguments: [lrange $argv $ndx end]"
+}
+# ndx no longer used for argv position from here
+
+gdsChk $gdsf
+
+# warning on combo of -tc & -km. If -km ok, open its output file.
+if {$enumFileKm ne {}} {
+    if {! $topcellTab} {
+	    puts "WARNING: ${::Prog}: with -tc cannot (-km) write klayout-marker-db"
+    } else {	
+	if {[catch {set enumOutKm [open $enumFileKm w]} msg]} {
+	    error "ERROR: ${::Prog}: failed to open-for-write '$enumFileKm' threw error, $msg"
+	}
+	puts "${::Prog}: enumerating each error bbox to: $enumFileKm"
+    }
+}
+
+# write a line with timestamp and all arguments to stdout (log)
+# (magic renames the TCL clock command)
+set clockp clock
+if {[info command $clockp] == {} && [info command orig_clock] != {}} {
+    set clockp orig_clock
+}
+set nowSec [$clockp seconds]
+set timestamp [$clockp format $nowSec -format "%Y-%m-%d.%T.%Z"]
+# TODO: quote logged argv here as needed so it's machine readable for replay purposes.
+puts "${::Prog}: timestamp: $timestamp, arguments: $argv"
+
+# just Manhattan is default, turn on euclidean, and log new mode
+drc euclidean on
+drc euclidean
+
+# 8.1.83 this worked:
+#    drc off; gds drccheck no;  gds read ... ; load topcell; select top cell; expand; drc check; drc update; drc listall count
+# By 8.2.64, that fails, the 'drc listall count' reports errors only in the top-cell, no subcells.
+# 8.1.83 & 8.2.193 this works (gds drccheck defaults to on anyway):
+#    drc off; gds drccheck yes; gds read ... ; load topcell; select top cell; expand; drc check; drc update; drc listall count
+#
+# But are we properly avoiding redundant drc runs?
+#
+# turn off background checker. We'll invoke checks explicitly.
+drc off
+gds drccheck yes
+puts "drc status (whether background checking enabled) is: [drc status]"
+puts "gds drccheck (whether gds-read marks new cells as need-drc) is: [gds drccheck]"
+
+# set user's drc style; set user's cifinput istyle
+# These are back-to-back without intervening status messages.
+# If both wrong their errors are back-to-back.
+set res {}
+set res [drc list style]
+if {$variant != {}} {
+    set allstyle [drc listall style]
+    set ndx [lsearch -exact $allstyle $variant]
+    if {$ndx < 0} {
+	puts "ERROR: ${::Prog}: drc style '$variant' not one of those available: $allstyle"
+	incr nbrErr
+    } else {
+	set res [drc list style $variant]
+    }
+}
+set res2 [cif list istyle]
+if {$istyle != {}} {
+    set allstyle [cif listall istyle]
+    set ndx [lsearch -exact $allstyle $istyle]
+    if {$ndx < 0} {
+	puts "ERROR: ${::Prog}: istyle '$istyle' not one of those available: $allstyle"
+	incr nbrErr
+    } else {
+	set res2 [cif istyle $istyle]
+    }
+}
+if {$res != {}} {
+    puts "drc style reports:\n$res"
+}
+if {$res2 != {}} {
+    puts "cif istyle reports:\n$res2"
+}
+
+# gds {path,polygon} subcell yes
+if         {$pathSub != 0} { gds    path subcells yes }
+puts "gds    path subcells: [gds    path subcells]"
+if      {$polySub != 0}    { gds polygon subcells yes }
+puts "gds polygon subcells: [gds polygon subcells]"
+
+# todo: this catch never happens. Need nicer error check of 'gds read' somehow. Can check for zero-sized file?
+# if use /dev/null for example, it prints its own error message, but no throw, no useful return value.
+puts         "doing: gds read $gdsf ..."
+if {[catch {set res [gds read $gdsf]} msg]} {
+    puts "ERROR: ${::Prog}: 'gds read $gdsf' threw error, $msg"
+    incr nbrErr
+}
+# nothing useful:
+# puts "gds-read res: $res"
+
+set topcells [cellname list top]
+set allcells [cellname list allcells]
+# puts "cellname-list-top from GDS is: $topcells"
+# puts "cellname-list-allcells from GDS are: $allcells"
+# filter (UNNAMED)
+set topcells [lsearch -exact -not -all -inline $topcells "(UNNAMED)"]
+set allcells [lsearch -exact -not -all -inline $allcells "(UNNAMED)"]
+set nbrAllCells [llength $allcells]
+
+if {$topcells == {}} {
+    puts "ERROR: ${::Prog}: GDS-read did not report any useful cell name(s) found."
+    incr nbrErr
+}
+
+if {$nbrErr > 0} {
+    return $nbrErr ;# outside of main, we print termination with errors message
+}
+
+if {$topc == {}} {
+    # try and infer topcell from cellname-list-top.
+    # presume its list of cells not placed anywhere else.
+    # todo: test with "library" GDS having more than one topcell
+    # here we just take the last entry
+    set topc [lindex $topcells end]
+    set topcStr $topc
+    puts "WARNING: auto-picked top-cell \"$topc\"; the topcells inferred from GDS are: $topcells"
+} else {
+    # verify input topc argument exists in GDS read result
+    set ndx [lsearch -exact $allcells $topc]
+    if {$ndx < 0} {
+	puts "ERROR: ${::Prog}: top-cell name: $topc, not found in GDS"
+	puts "info: top cells inferred from GDS are: $topcells"
+	puts "info: all cells inferred from GDS are: $allcells"
+	return [incr nbrErr] ;# outside of main, we print termination with errors message
+    }
+}
+
+puts "${::Prog}: running drc on -gds: $gdsf -topcell: $topcStr"
+reportTechFile
+
+# todo: need to error check load command somehow (no useful return value).
+# it can fail with error message (in log) like:
+#   File dne.mag couldn't be found
+#   Creating new cell
+if {[catch {set res [load $topc]} msg]} {
+    puts "ERROR: ${::Prog}: 'load $topc' threw error (maybe cellName not found in GDS?), $msg"
+    return [incr nbrErr] ;# outside of main, we print termination with errors message
+}
+# nothing useful:
+# puts "load $topc res: $res"
+
+if {$flatten} {
+    # delete (UNNAMED) if any.
+    set trg "(UNNAMED)"
+    if {[cellnameExists $trg]} {cellname delete $trg}
+
+    # rename top cell to (UNNAMED)
+    cellname rename $topc $trg
+
+    # now Edit Cell contents are original top cell, but under name (UNNAMED)
+    # flatten Edit-Cell into original top cell name
+    puts "${::Prog}: flattening..."
+    flatten $topc
+
+    # load and edit new version of top cell
+    load $topc
+
+    # crude way even in batch to determine the "current" cell; perhaps not yet the "Edit" cell
+    # WARNING, if topcell locked elsewhere or not writable, it can't become the "Edit" cell.
+    set topcw [cellname list window]
+    if {$topcw ne $topc} {
+	puts "ERROR: ${::Prog}: assertion failed, post-flatten, $topc, is not the current cell, 'cellname list window'=$topcw"
+	return [incr nbrErr] ;# outside of main, we print termination with errors message
+    }
+
+    # should not be necessary:
+    select top cell
+    edit
+
+    # crude way even in batch to determine the "current" cell; perhaps not yet the "Edit" cell
+    # WARNING, if topcell locked elsewhere or not writable, it can't become the "Edit" cell.
+    set topcw [cellname list window]
+    if {$topcw ne $topc} {
+	puts "ERROR: ${::Prog}: assertion-2 failed, post-flatten, $topc, is not the current cell, 'cellname list window'=$topcw"
+	return [incr nbrErr] ;# outside of main, we print termination with errors message
+    }
+}
+
+# Erase all preexisting *.drtcl first. Else when cell transitions from
+# dirty in previous run (leaving *.drtcl), to clean, the old *.drtcl
+# remains.
+# TODO: only delete *.drtcl of cells in 'cellname list allcells'?
+if {$doFeedback} {
+    set files [glob -nocomplain -types {f} -- ./*.drtcl]
+    if {$flatten} {
+	# only delete topcell's .drtcl in flatten mode, if there is one
+	set files [lsearch -all -inline -exact $files ./$topc.drtcl]
+    }
+    if {$files != {}} {
+	# TODO: detect/report failure details better here?
+	puts "${::Prog}: deleting preexisting *.drtcl"
+	set msg {}
+	set delfail [catch {eval {file delete} $files} msg]
+	set files [glob -nocomplain -types {f} -- ./*.drtcl]
+	if {$delfail || $files != {}} {
+	    puts "ERROR: ${::Prog}: failed to clean old ./*.drtcl files. $msg"
+	    incr nbrErr
+	}
+    }
+}
+
+# 1st "select top cell": without it drc-list-count is blank, and error count reduced.
+select top cell
+
+set bbox0 [view bbox]
+set outScale [cif scale out]
+
+# set bbox1 [view bbox]
+
+# "select top cell" and box [view bbox] should be equivalent in
+# placing a box around whole cell extent.
+# The box cmd ALSO prints lambda and micron user-friendly box data,
+# but it prints microns with not enough resolution,
+# (and no option to disable that flawed print out).
+#
+# todo: emulate box output in full, except for higher resolution,
+# here we only scale/print the overall bbox in microns.
+set bbs {}
+foreach oord $bbox0 {
+    lappend bbs [format "%.3f" [expr {$outScale * $oord}]]
+}
+puts "info: outScale: [format "%.6f" $outScale], view-bbox: $bbox0"
+puts "info: Root cell box: ([lindex $bbs 0]  [lindex $bbs 1]), ([lindex $bbs 2]  [lindex $bbs 3])"
+
+drc check
+drc catchup
+drc statistics
+drc rulestats
+# puts "doing plain: drc count"
+drc count
+
+# 2nd select top cell needed else error count may be reduced (why? bbox does not change due to DRC)
+select top cell
+
+set celllist        [drc listall count]
+set drcListCountTot [drc list count total]
+# puts stdout "(drc listall count)       is << " nonewline; puts stdout [list $celllist]                 nonewline; puts " >>"
+# puts stdout "(drc list count)          is << " nonewline; puts stdout [list [drc list count]]          nonewline; puts " >>"
+# puts stdout "(drc list    count total) is << " nonewline; puts stdout [list $drcListCountTot]          nonewline; puts " >>"
+# puts stdout "(drc listall count total) is << " nonewline; puts stdout [list [drc listall count total]] nonewline; puts " >>"
+# puts stdout "(drc list why)            is << " nonewline; puts stdout [list [drc list why]]            nonewline; puts " >>"
+# puts stdout "(drc listall why)         is << " nonewline; puts stdout [list [drc listall why]]         nonewline; puts " >>"
+
+set bbox2 [view bbox]
+if {$bbox2 != $bbox0} {
+    set bbs {}
+    foreach oord $bbox2 {
+	lappend bbs [format "%.3f" [expr {$outScale * $oord}]]
+    }
+    puts "info: outScale: [format "%.6f" $outScale], view-bbox: $bbox2"
+    puts "info: Root cell box2: ([lindex $bbs 0]  [lindex $bbs 1]), ([lindex $bbs 2]  [lindex $bbs 3])"
+}
+
+
+# canonicalize order of celllist, move topc to last (if present whatsoever).
+# force our own artificial entry for topc (zero errors) if not present (was clean)
+# puts "celllist before: $celllist"
+set nbrErrCells [llength $celllist]
+set topcPair [lsearch           -inline -index 0 -exact $celllist $topc]
+set celllist [lsearch -not -all -inline -index 0 -exact $celllist $topc]
+set celllist [lsort -index 0 -dictionary $celllist]
+if {$topcPair == {}} {
+    # puts "info: ${::Prog}: $topc clean, forcing celllist entry for it"
+    set topcPair [list $topc 0]
+}
+lappend celllist $topcPair
+# puts stdout "adjusted celllist(drc list count) is << " nonewline; puts stdout $celllist nonewline; puts " >>"
+
+array set kmErr2catNm {}
+array set kmErr2catDesc {}
+array set kmCell2item {}
+if {$celllist != {} && [info exists enumOutKm]} {
+    # Header example of .lyrdb klayout Marker format
+    # <?xml version="1.0" encoding="utf-8"?>
+    # <report-database>
+    # <description>Diff of 'x.gds, Cell RINGO' vs. 'x.gds[1], Cell INV2'</description>
+    # <original-file/>
+    # <generator/>
+    # <top-cell>RINGO</top-cell>
+    # <tags>
+    # <tag>
+    # <name>red</name>
+    # <description>Red flag</description>
+    # </tag>
+    # ... 
+    # </tags>
+
+    puts $enumOutKm {<?xml version="1.0" encoding="utf-8"?><report-database>}
+    puts $enumOutKm "<description>$topc DRC timestamp: $timestamp, arguments: $argv</description>"
+    puts $enumOutKm {<original-file/><generator/>}
+    puts $enumOutKm "<top-cell>$topc</top-cell>"
+    puts $enumOutKm {<tags/>}
+    puts $enumOutKm {<cells>}
+
+    # multiple <cells>...</cells> sections do accumulate, but cells and categories need
+    # to be defined before use in an item (specific error), and we know cell names here,
+    # so declare all cells to klayout here.
+    #
+    # Cell-specific header of klayout marker file
+    #  <cell>
+    #   <name>CELLNAME1</name>
+    #   <variant>1</variant>               (don't need)
+    #  </cell>
+    #
+    foreach pair $celllist {
+	set acell [lindex $pair 0]
+
+	# for -tt, no subcell error-detail: don't write subcells in <cells>...</cells> section.
+	if {$acell ne $topc && ! $subcellTab} { continue }
+
+	puts $enumOutKm "  <cell><name>$acell</name></cell>"
+	set kmCell2item($acell) {}
+    }
+    puts $enumOutKm {</cells>}
+}
+
+# loop over celllist
+set gtotal 0
+set gcells 0
+set lumpedHeader 0
+foreach pair $celllist {
+    set acell [lindex $pair 0]
+    set acount [lindex $pair 1]
+
+    if {$acell ne $topc && ! $subcellTab} {
+	if {! $lumpedHeader} {
+	    puts "--- #err|cell, lumped total counts"
+	    set lumpedHeader 1
+	}
+	puts "[format {%8d} $acount] $acell"
+	incr gcells
+	incr gtotal $acount
+	continue
+    }
+    if {$acell eq $topc && ! $topcellTab} {
+	if {! $lumpedHeader} {
+	    puts "--- #err|cell, lumped total counts"
+	    set lumpedHeader 1
+	}
+	puts "[format {%8d} $acount] $acell"
+	incr gcells
+	incr gtotal $acount
+	continue
+    }
+    puts ""
+
+    # todo: need useful error check of load command
+    if {[catch {set res [load $acell]} msg]} {
+	puts "ERROR: ${::Prog}: 'load $acell' threw error, $msg"
+	return [incr nbrErr] ;# outside of main, we print termination with errors message
+    }
+
+    # instead use quiet version for per-cell selects
+    select top cell
+
+    set drcListCountTot [drc listall count total]
+
+    # enumerate errors under box, plain "drc why" only reports unique types, no quantities
+    # as-yet-undocumented "drc listall why" will give: {errStr1 {errBox1 ...} errStr2 {errBox1 ...} ... }
+    set pareto {}
+    set total 0
+    set enumTotal 0
+    set types 0
+    set typeDup 0
+    set dups 0
+
+    set fbOut {}
+    if {$acount != 0} {
+	# file path for feedback, keep in CWD
+	if {$doFeedback && $fbOut == {}} {
+	    set fbOut "./$acell.drtcl"
+	    if {![file writable $fbOut] &&
+		([file exists $fbOut] || ![file writable [file dir $fbOut]])} {
+		puts stderr "ERROR: ${::Prog}: feedback output not writable, $fbOut"
+		incr nbrErr
+		set fbOut {}
+	    } elseif {[catch {set outfb [open $fbOut w]} msg]} {
+		puts stderr "ERROR: ${::Prog}: failed to truncate previous feedback output, $fbOut : $msg"
+		incr nbrErr
+		set fbOut {}
+	    }
+	}
+
+	foreach {str boxes} [drc listall why] {
+	    # sort errors
+	    set boxes [lsort -dictionary $boxes]
+	    # for our pareto, gather data
+	    set this [llength $boxes]
+	    incr total $this
+	    incr types
+	    lappend pareto [list $this $str]
+
+	    # for enumOut, emulate formatting of $CAD_ROOT/magic/tcl/drc.tcl, which is
+	    # not tk pure: fails with complaint about winfo
+	    # note: we walk these errors also in order to count/report stats on duplicates, even if not outputing enumerations
+	    if {[info exists enumOut]} {
+		if {$types == 1} {
+		    puts $enumOut "[join $pair]\n----------------------------------------"
+		}
+		puts $enumOut "${str}\n----------------------------------------"
+	    }
+	    if {[info exists enumOutL]} {
+		if {$types == 1} {
+		    puts $enumOutL "[join $pair]\n----------------------------------------"
+		}
+		puts $enumOutL "${str}\n----------------------------------------"
+	    }
+	    if {[info exists enumOutKm]} {
+		# category names must be declared all together up front before use in items
+		# so we only store their names (error strings) and error detail (items)
+		# to dump after all cells and errors are processed.
+		# TODO: Only quote catName in item if embeds dot, instead of full-time
+		# TODO: test klayout handles literal (non-entity) single-quote in double-quoted name
+		set strKmNm   $str
+		set strKmDesc $str
+		regsub -all -- {&} $strKmDesc {\&amp;} strKmDesc  ;# perhaps not needed; just in case
+		regsub -all -- {<} $strKmDesc {\&lt;}  strKmDesc  ;# description does not have such bug, so use correct entity
+		regsub -all -- {>} $strKmDesc {\&gt;}  strKmDesc  ;# perhaps not needed; just in case
+		regsub -all -- {&}  $strKmNm  {-and-} strKmNm    ;# perhaps not needed; just in case
+		regsub -all -- {>}  $strKmNm  {-gt-}  strKmNm    ;# perhaps not needed; just in case
+		regsub -all -- {<}  $strKmNm  {-lt-}  strKmNm    ;# catName klayout bug: info win truncates at '<' as &lt; entity
+		regsub -all -- "\"" $strKmNm  {'}     strKmNm    ;# we dqoute each catNm in item, so change embedded double to single
+		set kmErr2catNm($str)   $strKmNm
+		set kmErr2catDesc($str) $strKmDesc
+		#
+		# example klayout Marker format, header of one item (one error instance)
+		#  <item>
+		#   <tags/>               (don't need?)
+		#   <image/>               (don't need?)
+		#   <category>'DRC-MSG-STR'</category>       (cat1.cat2 path delimit by dot: names with dot need single|double quotes)
+		#   <cell>RINGO:1</cell>                     (don't need :N variant suffix)
+		#   <visited>false</visited>                  (optional? start with false?)
+		#   <multiplicity>1</multiplicity>           (not boolean, if error "represents" more that are NOT enumerated)
+		#   <values> ... </values>
+		#  </item>
+
+		set itemStr "<item><category>\"$strKmNm\"</category><cell>$acell</cell><values>"
+	    }
+	    set lastq {}
+	    set thisDup 0
+	    foreach quad $boxes {
+		set quadUM {}
+		set kmBoxUM {}
+		foreach coord $quad {
+		    set valum [expr {$coord * $outScale}]
+		    set valumf [format "%.3f" $valum]
+		    lappend quadUM "${valumf}um"
+		    lappend kmBoxUM ${valumf}
+		}
+		set dup [expr {$quad == $lastq}]
+		incr thisDup $dup
+		set line $quadUM
+		if {[info exists enumOut]} {
+		    if {$dup} {
+			puts $enumOut "[join $line] #dup"
+		    } else {
+			puts $enumOut [join $line]
+		    }
+		}
+		if {[info exists enumOutL]} {
+		    if {$dup} {
+			puts $enumOutL "$quad #dup"
+		    } else {
+			puts $enumOutL $quad
+		    }
+		}
+		if {[info exists enumOutKm]} {
+		    #    <value>text: 'item: polygon'</value>                          (text is optional? Repeat the box coordinates here in um?)
+		    #    <value>polygon: (1.4,1.8;-1.4,1.8;-1.4,3.8;1.4,3.8)</value>
+		    #    <value>box: (1.4,1.8;-1.4,3.8)</value>
+		    #   </values>
+		    set kmItem $itemStr
+		    append kmItem " <value>box: ([lindex $kmBoxUM 0],[lindex $kmBoxUM 1];[lindex $kmBoxUM 2],[lindex $kmBoxUM 3])</value>"
+		    if {$dup} {
+			append kmItem " <value>text: 'dup'</value>"
+		    }
+		    append kmItem " </values></item>"
+		    lappend kmCell2item($acell) $kmItem
+		}
+		if {$fbOut != {}} {
+		    set line [join $quadUM]
+		    regsub -all -- "(\[\[\"\$\\\\])" $str {\\\1} strdq
+		    puts $outfb "[concat box $line]"                nonewline
+		    puts $outfb " ; feedback add \"$strdq\" medium" nonewline
+		    if {$dup} {
+			puts $outfb " ;#dup"
+		    } else {
+			puts $outfb ""
+		    }
+		}
+
+		incr enumTotal
+		set lastq $quad
+	    }
+	    if {$thisDup} {
+		incr typeDup
+		incr dups $thisDup
+	    }
+	    if {[info exists enumOut]} {
+		puts $enumOut "----------------------------------------\n"
+	    }
+	    if {[info exists enumOutL]} {
+		puts $enumOutL "----------------------------------------\n"
+	    }
+	}
+    }
+
+    if {$fbOut != {}} {
+	close $outfb
+	set outfb {}
+    }
+
+    set pareto [lsort -integer -decreasing -index 0 $pareto]
+    if {$total > 0} {
+	puts "--- #err|description, table for cell: $acell"
+    }
+    foreach pair $pareto {
+	puts "[format {%8d} [lindex $pair 0]] [lindex $pair 1]"
+    }
+    if {$typeDup} {
+	puts "[format {%8d} $dups] total duplicate error(s) among $typeDup error type(s), cell: $acell"
+    }
+    puts "[format {%8d} $total] total error(s) among $types error type(s), cell: $acell"
+    # add to grand-totals
+    incr gcells
+    incr gtotal $total
+
+    # always compare the total from the enum to the pareto as error check
+    if {$total != $enumTotal} {
+	puts "ERROR: ${::Prog}: cell: $acell, internal error, pareto vs enum count mismatch: $total != $enumTotal"
+	incr nbrErr
+    }
+    # wish to compare the drc-list-count-total to the pareto total.
+    # Per te 2014-08-27 : it is not an error.
+    if {$total != $drcListCountTot} {
+	# puts "info: ${::Prog}: cell: $acell, drc-list-count-total vs drc-listall-why mismatch {drc list count total} gave $drcListCountTot, but {drc listall why} gave $total"
+    }
+}
+
+# grand totals
+puts "[format {%8d} $nbrErrCells] of $nbrAllCells cell(s) report error(s)"
+puts "[format {%8d} $gtotal] grand-total error(s) across $gcells cell(s)"
+
+if {[info exists enumOut]} {
+    close $enumOut
+}
+if {[info exists enumOutL]} {
+    close $enumOutL
+}
+if {[info exists enumOutKm]} {
+    # declare all category names and descriptions, note '<' in name vs description are represented differently
+    #
+    # <categories><category><name>layerN width -lt- 1.0um</name>
+    # <description>layerN width &lt; 1.0um</description></category>
+    # <category> ... </category></categories>
+    #
+    puts $enumOutKm "<categories>"
+    foreach errStr [array names kmErr2catNm] {
+	set nm   $kmErr2catNm($errStr)
+	set desc $kmErr2catDesc($errStr)
+	puts $enumOutKm "  <category><name>$nm</name><description>$desc</description></category>"
+    }
+    puts $enumOutKm "</categories>"
+
+    # dump all items (after all cells and all categories have been defined up front)
+    puts $enumOutKm "<items>"
+    foreach {acell items} [array get kmCell2item] {
+	foreach item $items {
+	    puts $enumOutKm $item
+	}
+    }
+    puts $enumOutKm "</items>"
+
+    # footer example .lyrdb klayout Marker file
+    # </report-database>
+    puts $enumOutKm {</report-database>}
+    close $enumOutKm
+}
+# todo: implement super-pareto, ranked table of SUM of all DRC errs/counts from ALL cells.
+# (It still would not reflect as-if-flat hierarchical expansion due to repetition of instances).
+
+set nbrErr ;# return value
+} ;# end main
+
+# non-zero exit-status on errors, either if thrown by main, or counted and returned by main
+set nbrErr 0
+if {[catch {set nbrErr [main $argv]} msg]} {
+    puts stderr $msg
+    set nbrErr 1
+} elseif {$nbrErr > 0} {
+    puts "ERROR: ${::Prog}: script terminated with errors reported above."
+}
+exit $nbrErr
+
+# for emacs syntax-mode:
+# Local Variables:
+# mode:tcl
+# End:
diff --git a/caravel/utils/parse_klayout_xor_log.py b/caravel/utils/parse_klayout_xor_log.py
new file mode 100644
index 0000000..d93fb2c
--- /dev/null
+++ b/caravel/utils/parse_klayout_xor_log.py
@@ -0,0 +1,43 @@
+# SPDX-FileCopyrightText: 2020 Efabless Corporation
+#
+# Licensed under the Apache License, Version 2.0 (the "License");
+# you may not use this file except in compliance with the License.
+# You may obtain a copy of the License at
+#
+#      http://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing, software
+# distributed under the License is distributed on an "AS IS" BASIS,
+# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+# See the License for the specific language governing permissions and
+# limitations under the License.
+# SPDX-License-Identifier: Apache-2.0
+
+import argparse
+import re
+
+parser = argparse.ArgumentParser(
+    description='extracts the total xor differnces from an xor log')
+
+parser.add_argument('--log_file', '-l',required=True,
+                    help='log file')
+
+parser.add_argument('--output', '-o', required=True,
+                    help='output file to store results')
+
+args = parser.parse_args()
+log_file_name = args.log_file
+out_file_name = args.output
+
+string = "XOR differences:"
+pattern = re.compile(r'\s*%s\s*([\d+]+)' % string)
+tot_cnt = 0
+with open(log_file_name, "r") as f:
+    for line in f:
+        m = pattern.match(line)
+        if m:
+            tot_cnt += int(m.group(1))
+
+outFileOpener = open(out_file_name, "w")
+outFileOpener.write("Total XOR differences = "+ str(tot_cnt))
+outFileOpener.close()
diff --git a/caravel/utils/scrotLayout.py b/caravel/utils/scrotLayout.py
new file mode 100644
index 0000000..6eb282e
--- /dev/null
+++ b/caravel/utils/scrotLayout.py
@@ -0,0 +1,59 @@
+# SPDX-FileCopyrightText: 2020 Efabless Corporation
+#
+# Licensed under the Apache License, Version 2.0 (the "License");
+# you may not use this file except in compliance with the License.
+# You may obtain a copy of the License at
+#
+#      http://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing, software
+# distributed under the License is distributed on an "AS IS" BASIS,
+# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+# See the License for the specific language governing permissions and
+# limitations under the License.
+# SPDX-License-Identifier: Apache-2.0
+
+import pya
+import re
+import os
+
+WIDTH = 2048
+HEIGHT = 2048
+
+app = pya.Application.instance()
+win = app.main_window()
+
+# Load technology file
+print('[INFO] Reading tech file: ' + str(tech_file))
+tech = pya.Technology()
+tech.load(tech_file)
+
+layoutOptions = tech.load_layout_options
+
+# Load def file in the main window
+print('[INFO] Reading Layout file: ' + str(input_layout))
+cell_view = win.load_layout(input_layout, layoutOptions, 0)
+layout_view = cell_view.view()
+
+layout_view.load_layer_props(os.path.splitext(tech_file)[0]+'.lyp')
+
+layout_view.max_hier()
+# layout_view.clear_layers()
+
+# Hide layers with these purposes
+hidden_purposes = [0, 4, 5]
+
+li = layout_view.begin_layers()
+while not li.at_end():
+    lp = li.current()
+    if lp.source_datatype in hidden_purposes:
+        new_lp = lp.dup()
+        new_lp.visible = False
+        layout_view.set_layer_properties(li, new_lp)
+
+    li.next()
+
+print("[INFO] Writing out PNG screenshot '{0}'".format(input_layout+".png"))
+layout_view.save_image(input_layout+".png", WIDTH, HEIGHT)
+print("Done")
+app.exit(0)
diff --git a/caravel/utils/scrotLayout.sh b/caravel/utils/scrotLayout.sh
new file mode 100644
index 0000000..3b81a3f
--- /dev/null
+++ b/caravel/utils/scrotLayout.sh
@@ -0,0 +1,32 @@
+#!/bin/sh
+# SPDX-FileCopyrightText: 2020 Efabless Corporation
+#
+# Licensed under the Apache License, Version 2.0 (the "License");
+# you may not use this file except in compliance with the License.
+# You may obtain a copy of the License at
+#
+#      http://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing, software
+# distributed under the License is distributed on an "AS IS" BASIS,
+# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+# See the License for the specific language governing permissions and
+# limitations under the License.
+# SPDX-License-Identifier: Apache-2.0
+
+set -e
+
+: ${1?"Usage: $0 tech_file input"}
+: ${2?"Usage: $0 tech_file input"}
+
+echo "Using Techfile: $1"
+echo "Using layout file: $2"
+
+# The -a here is necessary to handle race conditions.
+# This limits the max number of possible jobs to 100.
+xvfb-run -a klayout -z \
+    -rd input_layout=$2 \
+    -rd tech_file=$1 \
+    -rm $(dirname $0)/scrotLayout.py
+
+exit 0
diff --git a/caravel/utils/xor.drc b/caravel/utils/xor.drc
new file mode 100644
index 0000000..6caee91
--- /dev/null
+++ b/caravel/utils/xor.drc
@@ -0,0 +1,42 @@
+# A general XOR script
+# (https://www.klayout.de/forum/discussion/100/xor-vs-diff-tool)
+# This script uses KLayout's DRC language to implement a generic
+# XOR between two layouts. The name of the layouts is given
+# in $a and $b.
+
+# For layout-to-layout XOR with multiple cores, run this script with
+#   ./klayout -r xor.drc -rd thr=NUM_CORES -rd top_cell=TOP_CELL_NAME -rd a=a.gds -rd b=b.gds -rd ol=xor.gds -zz
+# (replace NUM_CORES by the desired number of cores to utilize
+
+# enable timing output
+verbose
+
+# set up input a
+a = source($a, $top_cell)
+
+# set up input b
+b = source($b, $top_cell)
+
+$o && $ext != "gds" && report("XOR #{$a} vs. #{$b}", $o)
+$ol && $ext == "gds" && target($ol, $co || "XOR")
+
+$thr && threads($thr) || threads(2)
+
+# collect all common layers
+layers = {}
+[ a.layout, b.layout ].each do |ly|
+  ly.layer_indices.each do |li|
+    i = ly.get_info(li)
+    layers[i.to_s] = i
+  end
+end
+
+# perform the XOR's
+layers.keys.sort.each do |l|
+  i = layers[l]
+  info("--- Running XOR for #{l} ---")
+  x = a.input(l) ^ b.input(l)
+  info("XOR differences: #{x.data.size}")
+  $o && $ext != "gds" && x.output(l, "XOR results for layer #{l} #{i.name}")
+  $ol && $ext == "gds" && x.output(i.layer, i.datatype, i.name)
+end
diff --git a/caravel/utils/xor.sh b/caravel/utils/xor.sh
new file mode 100644
index 0000000..44800d6
--- /dev/null
+++ b/caravel/utils/xor.sh
@@ -0,0 +1,36 @@
+#!/bin/sh
+# SPDX-FileCopyrightText: 2020 Efabless Corporation
+#
+# Licensed under the Apache License, Version 2.0 (the "License");
+# you may not use this file except in compliance with the License.
+# You may obtain a copy of the License at
+#
+#      http://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing, software
+# distributed under the License is distributed on an "AS IS" BASIS,
+# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+# See the License for the specific language governing permissions and
+# limitations under the License.
+# SPDX-License-Identifier: Apache-2.0
+
+: ${1?"Usage: $0 file1.gds file2.gds <top_level_module_name> output.gds|markers.xml"}
+: ${2?"Usage: $0 file1.gds file2.gds <top_level_module_name> output.gds|markers.xml"}
+: ${3?"Usage: $0 file1.gds file2.gds <top_level_module_name> output.gds|markers.xml"}
+: ${4?"Usage: $0 file1.gds file2.gds <top_level_module_name> output.gds|markers.xml"}
+
+
+echo "First Layout: $1"
+echo "Second Layout: $2"
+echo "Design Name: $3"
+echo "Output GDS will be: $4"
+
+xvfb-run -a klayout -r $(dirname $0)/xor.drc \
+    -rd top_cell=$3 \
+    -rd a=$1 \
+    -rd b=$2 \
+    -rd thr=$(nproc) \
+    -rd ol=$4 \
+    -rd o=$4 \
+    -rd ext=${4##*.} \
+    -zz