SPICE general-purpose, open-source analog electronic circuit simulator. It stands for Simulation Program with Integrated Circuit Emphasis.
ngspice is a successor, and is easily installable on Linux. It’s the simulator I’ve used to explore the Skywater 130 PDK.
Here’s an example spice simulation file that I used to simulate the inverter I drew.
And here’s a nice demo of me showing how a flip-flop works by simulating a Sky130 D type flip flop with SPICE.
The Discord channel is my favorite thing, I get my hands on right before I sleep - there's a lot of cool things and people are so awesome, they're really helpful. The community side of the course is an important part of it.