@docRekd@publicvoit Of course. It's not a general solution to be able to do Python dev on NixOS. One needs a separate nix file per project (that alone is an absolute no-go). Even if you take the time and try to make one, still no guarantee that it works (even with preferWheels=true!). Weird errors arise with nix' typical awful error messages and at this point it's not useable for general Python dev. Maybe for specific standalone Python projects you want to #nix-ify.