hi, @User,if you clone the xschem_sky130 repository and start xschem from the xschem_sky130 directory (as explained in the README) xschem will show a top schematic with some circuits ready for simulation. what tou need to do is to set up the path ngspice will look for for spice models, i have installed the skywater-pdk stuff into my home directory (~/skywater-pdk) so the analog models are under ~/skywater-pdk/sky130_fd_pr. If you have a different path you need to change accordingly. Usually you just need a '.lib /path/to/skywater-pdk/sky130_fd_pr/models/sky130.lib.spice' . Also see here the xschem manual. May be i will add a specific (video?) tutorial for sky130.