diff --git a/docs/sim/ngspice.rst b/docs/sim/ngspice.rst
new file mode 100644
index 0000000..0136168
--- /dev/null
+++ b/docs/sim/ngspice.rst
@@ -0,0 +1,2 @@
+TODO: sim/ngspice
+=================
diff --git a/docs/sim/spectre.rst b/docs/sim/spectre.rst
new file mode 100644
index 0000000..5090786
--- /dev/null
+++ b/docs/sim/spectre.rst
@@ -0,0 +1,2 @@
+TODO: sim/spectre
+=================
diff --git a/docs/sim/spice.rst b/docs/sim/spice.rst
new file mode 100644
index 0000000..e69de29
--- /dev/null
+++ b/docs/sim/spice.rst