flake.nix

{
  description = "demoapp";

  inputs = {
    nixpkgs.url = "github:NixOS/nixpkgs/nixos-unstable";
    flake-parts.url = "github:hercules-ci/flake-parts";
    rust-overlay.url = "github:oxalica/rust-overlay";
    systems = {
      url = "github:nix-systems/default";
      flake = false;
    };
  };

  outputs = inputs @ { flake-parts, ... }:
    flake-parts.lib.mkFlake { inherit inputs; } {
      imports = [ ];

      systems = import inputs.systems;
      perSystem =
        { config
        , self'
        , inputs'
        , pkgs
        , system
        , ...
        }:
        let
          rust-toolchain =
            pkgs.rust-bin.fromRustupToolchainFile ./toolchain.toml;

            buildDeps = with pkgs; [
              ncurses
              gcc
            ];

          mkDevShell = rust-toolchain:
            pkgs.mkShell {
              LD_LIBRARY_PATH = "${pkgs.lib.makeLibraryPath buildDeps}:$LD_LIBRARY_PATH";
              packages = buildDeps ++ [ rust-toolchain ];
            };
        in
        {
          _module.args.pkgs = import inputs.nixpkgs {
            inherit system;
            overlays = [ (import inputs.rust-overlay) ];
          };

          formatter = pkgs.alejandra;

          devShells.default = self'.devShells.msrv;
          devShells.msrv = mkDevShell rust-toolchain;
          devShells.stable = mkDevShell pkgs.rust-bin.stable.latest.default;
          devShells.nightly =
            mkDevShell (pkgs.rust-bin.selectLatestNightlyWith
              (toolchain: toolchain.default));
        };
    };
}