What I like most about nixos is that you can have deterministically cached packages you don't need to rebuild every time in your ci.

It's also simple to setup dev environments with nix.

Nix in CI seems like a really excellent match. I don’t care much about the ATproto space - but Tangled has built their CI system on Nix and I find that really compelling. CI Caching is just awful with GitHub actions - so it made me disappointed that Forgejo went that route.