Having a flake check for typechecking a project.

[vic]

It would also be nice to have instruction on how to add a flake check derivation that fails if the project is not correct. Maybe could be shown at the example flake.nix

[ryanrasti]

Good idea -- PRs welcome!

[jkuball]

Hey @vic,

I am using flake-parts, it should be analogue to all other flake frameworks.

https://github.com/jkuball/nvim-flake/blob/5c58c735aade65abe56718ec5c7321a16b05aa24/flake.nix#L50:

checks."typenix" = pkgs.runCommand "typenix-check"
  { nativeBuildInputs = [ pkgs.typenix ]; }
  ''
    typenix -p ${self}
    touch $out
  '';

It's probably not "the best way" to do it, and I am also not sure if one should write it exacly like this into the projects README, but it definitely works and is good enough to paste into an issue one stumbles randomly upon. 😇 You just need to have an tsconfig.json. One could also create this only for the derivation, but I would argue that it would be better to add it to the whole project, so your flake check and your LSP uses the same core.