greatbarriergeek

I'd recommend Obsidian. Free and perfect for making and organising markdown notes, plus heaps of community extensions. And out-of-the-box you can make "canvas" pages where you can draw diagrams.

Kagi

Couple of ideas: At the end of the first quarter they were originally going to release the alpha for their Cosmic DE which got postponed. They also had the LinuxFest NorthWest conference they presented at.

GPT Unicorn is one that's been going on a while. There's a link to the talk on that website that's a pretty good watch too.