Haskell flake

flake.nix

{
  description = "Haskell";

  inputs = {
    nixpkgs.url = "github:nixos/nixpkgs/haskell-updates";
    flake-utils.url = "github:numtide/flake-utils";
  };

  outputs = { self, nixpkgs, flake-utils }:
    flake-utils.lib.eachDefaultSystem (system:
      let
        pkgs = nixpkgs.legacyPackages.${system};

        haskellPackages = pkgs.haskell.packages.ghc9101;

        packageName = "aoc";
      in
      {
        packages.${packageName} =
          haskellPackages.callCabal2nix packageName self rec {
            # Dependency overrides go here
          };

        packages.default = self.packages.${system}.${packageName};
        defaultPackage = self.packages.${system}.default;

        devShells.default = pkgs.mkShell {
          buildInputs = with haskellPackages; [
            ghc
            haskell-language-server
            ghcid
            cabal-install
          ];
        };
      }
    );
}