Added the layouts used for DRC ruleset development to sky130/custom/drc/.
diff --git a/sky130/custom/drc/poly.mag b/sky130/custom/drc/poly.mag
new file mode 100644
index 0000000..d76b0f6
--- /dev/null
+++ b/sky130/custom/drc/poly.mag
@@ -0,0 +1,259 @@
+magic
+tech sky130A
+magscale 1 2
+timestamp 1602986603
+<< error_p >>
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+<< nwell >>
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+<< nmos >>
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+<< pmos >>
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+<< pmoslvt >>
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+<< ndiff >>
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+<< pdiff >>
+rect 1730 2052 1870 2342
+rect 1920 2052 2012 2342
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+rect 5530 836 5682 894
+rect 3544 -379 4304 -246
+<< psubdiff >>
+rect 5012 2158 5182 2254
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+<< nsubdiff >>
+rect 2238 2230 2415 2276
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+<< psubdiffcont >>
+rect 2036 492 2144 604
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+<< nsubdiffcont >>
+rect 2248 2076 2408 2230
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+<< poly >>
+rect 1870 2342 1920 2452
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+<< npolyres >>
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+rect 3574 -191 3640 221
+rect 3556 -1099 3622 -686
+<< ppolyres >>
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+rect 3846 -185 3916 243
+rect 3828 -1093 3898 -665
+<< xpolyres >>
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+rect 4190 -191 4262 237
+rect 4172 -1099 4244 -671
+<< locali >>
+rect 4640 2540 4704 2564
+rect 4640 2452 4704 2476
+rect 2248 2230 2408 2270
+rect 2248 2040 2408 2076
+rect 2048 1184 2156 1204
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+<< labels >>
+flabel comment s 292 2248 292 2248 0 FreeSans 800 0 0 0 Poly
+flabel comment s 1878 1862 1878 1862 0 FreeSans 560 0 0 0 poly.1b
+flabel comment s 1272 1850 1272 1850 0 FreeSans 560 0 0 0 poly.1a
+flabel comment s 2766 1836 2766 1842 0 FreeSans 560 0 0 0 poly.2
+flabel comment s 3482 1892 3482 1894 0 FreeSans 560 0 0 0 poly.3
+flabel comment s 4264 1904 4264 1904 0 FreeSans 560 0 0 0 poly.4
+flabel comment s 5030 1944 5030 1944 0 FreeSans 560 0 0 0 poly.5
+flabel comment s 484 1360 490 1360 0 FreeSans 560 0 0 0 Correct_by_design
+flabel comment s 1874 236 1874 242 0 FreeSans 560 0 0 0 poly.6
+flabel comment s 2612 244 2612 250 0 FreeSans 560 0 0 0 poly.7
+flabel comment s 3090 248 3090 254 0 FreeSans 560 0 0 0 poly.8
+flabel comment s 3916 482 3916 488 0 FreeSans 560 0 0 0 poly.9
+flabel comment s 4792 200 4792 200 0 FreeSans 560 0 0 0 poly.10
+flabel comment s 5428 198 5428 198 0 FreeSans 560 0 0 0 poly.11
+flabel comment s 410 1196 410 1196 0 FreeSans 560 0 0 0 poly.12
+flabel comment s 376 1026 376 1026 0 FreeSans 560 0 0 0 poly.15
+flabel comment s 408 552 408 552 0 FreeSans 560 0 0 0 Not implemented
+flabel comment s 476 334 476 334 0 FreeSans 560 0 0 0 poly.16
+<< end >>
