I found this informative post that mentions Kazan and a whole bunch of other stuff. It looks like *many* APIs can be emulated on top of Vulkan, although performance is not evaluated.
<https://synappsis.wordpress.com/2017/06/03/opengl-over-vulkan-dev/>
+
+# Free Silicon Conference
+
+The conference brought together experts and enthusiasts who want to build a complete Free and Open Source CAD ecosystem for designing analog and digital integrated circuits.
+The conference covered the full spectrum of the design process, from system architecture, to layout and verification.
+
+<https://wiki.f-si.org/index.php/FSiC2019#Foundries.2C_PDKs_and_cell_libraries>
+
+LIP6's Coriolis - a set of backend design tools: <https://www-soc.lip6.fr/equipe-cian/logiciels/coriolis/>
+
+Note: The rest of LIP6's website is in French, but there is a UK flag in the corner that gives the English version.
+
+KLayout - Layout viewer and editor: <https://www.klayout.de/>
+
+# The OpenROAD Project
+
+OpenROAD seeks to develop and foster an autonomous, 24-hour, open-source layout generation flow (RTL-to-GDS).
+
+<https://theopenroadproject.org/>