{
  description = "devenv";

  inputs = {
    nixpkgs.url      = "github:NixOS/nixpkgs/nixos-unstable";
    flake-utils.url  = "github:numtide/flake-utils";
    rust-overlay.url = "github:oxalica/rust-overlay";
  };

  outputs = { self, nixpkgs, rust-overlay, flake-utils, ... }:
    flake-utils.lib.eachDefaultSystem (system:
      let
        overlays = [ (import rust-overlay) ];
        pkgs = import nixpkgs {
          inherit system overlays;
        };
        rust = pkgs.makeRustPlatform {
          cargo = pkgs.rust-bin.stable."${versions.rust}".default;
          rustc = pkgs.rust-bin.stable."${versions.rust}".default;
        };
        versions = {
          rust = "1.82.0";
        };
      in with pkgs; {
        devShells.default = mkShell {
          buildInputs = [
            # pkg
            pkg-config
            # rust
            rust-bin.stable."${versions.rust}".default  
            rust-bin.nightly.latest.default
            # tools
            helix
            gitui

            # rust packages / programs
            (rust.buildRustPackage rec {
              pname = "hoox";
              version = "0.3.0";
              doCheck = false;
              src = fetchCrate {
                inherit pname version;
                hash = "sha256-OFeut8JtyLqIUDH3JhVm9Gmpu+3zuaGx1I9dD8NWDl8=";
              };
              cargoHash = "sha256-h+2y+1iRb+hdbFzRR3fgZ5yznT+sOgIezZRIuZnfRkc=";
            })
         ];

          shellHook = ''
            export RUST_LOG=debug
            export RUST_BACKTRACE=1

            # make sure hooks are installed
            hoox init

            printf "Versions:\n"
            printf "$(rustc --version)\n"
            printf "$(hx --version)\n"
            printf "$(gitui --version)\n"
            printf "\n"
          '';
        };
      }
    );
}