flake.nix

{
  description =
    "Ready-made templates for easily creating flake-driven environments";

  inputs.nixpkgs.url = "github:NixOS/nixpkgs/nixpkgs-unstable";

  outputs = { self, nixpkgs }:
    let
      overlays = [
        (final: prev:
          let exec = pkg: "${prev.${pkg}}/bin/${pkg}";
          in {
            format = prev.writeScriptBin "format" ''
              ${exec "nixpkgs-fmt"} **/*.nix
            '';
            dvt = prev.writeScriptBin "dvt" ''
              if [ -z $1 ]; then
                echo "no template specified"
                exit 1
              fi

              TEMPLATE=$1

              ${exec "nix"} \
                --experimental-features 'nix-command flakes' \
                flake init \
                --template \
                "github:the-nix-way/dev-templates#''${TEMPLATE}"
            '';
            update = prev.writeScriptBin "update" ''
              for dir in `ls -d */`; do # Iterate through all the templates
                (
                  cd $dir
                  ${exec "nix"} flake update # Update flake.lock
                  ${
                    exec "nix"
                  } flake check  # Make sure things work after the update
                )
              done
            '';
          })
      ];
      supportedSystems =
        [ "x86_64-linux" "aarch64-linux" "x86_64-darwin" "aarch64-darwin" ];
      forEachSupportedSystem = f:
        nixpkgs.lib.genAttrs supportedSystems
          (system: f { pkgs = import nixpkgs { inherit overlays system; }; });
    in
    {
      devShells = forEachSupportedSystem ({ pkgs }: {
        default = pkgs.mkShell { packages = with pkgs; [ format update ]; };
      });

      packages = forEachSupportedSystem ({ pkgs }: rec {
        default = dvt;
        inherit (pkgs) dvt;
      });
    }

    //

    {
      templates = rec {
        clojure = {
          path = ./clojure;
          description = "Clojure development environment";
        };

        csharp = {
          path = ./csharp;
          description = "C# development environment";
        };

        cue = {
          path = ./cue;
          description = "Cue development environment";
        };

        dhall = {
          path = ./dhall;
          description = "Dhall development environment";
        };

        elixir = {
          path = ./elixir;
          description = "Elixir development environment";
        };

        elm = {
          path = ./elm;
          description = "Elm development environment";
        };

        gleam = {
          path = ./gleam;
          description = "Gleam development environment";
        };

        go = {
          path = ./go;
          description = "Go (Golang) development environment";
        };

        hashi = {
          path = ./hashi;
          description = "HashiCorp DevOps tools development environment";
        };

        haskell = {
          path = ./haskell;
          description = "Haskell development environment";
        };

        java = {
          path = ./java;
          description = "Java development environment";
        };

        kotlin = {
          path = ./kotlin;
          description = "Kotlin development environment";
        };

        latex = {
          path = ./latex;
          description = "LaTeX development environment";
        };

        nickel = {
          path = ./nickel;
          description = "Nickel development environment";
        };

        nim = {
          path = ./nim;
          description = "Nim development environment";
        };

        nix = {
          path = ./nix;
          description = "Nix development environment";
        };

        node = {
          path = ./node;
          description = "Node.js development environment";
        };

        opa = {
          path = ./opa;
          description = "Open Policy Agent development environment";
        };

        php = {
          path = ./php;
          description = "PHP development environment";
        };

        protobuf = {
          path = ./protobuf;
          description = "Protobuf development environment";
        };

        pulumi = {
          path = ./pulumi;
          description = "Pulumi development environment";
        };

        purescript = {
          path = ./purescript;
          description = "Purescript development environment";
        };

        python = {
          path = ./python;
          description = "Python development environment";
        };

        python-venv = {
          path = ./python-venv;
          description = "Python development environment";
        };

        ruby = {
          path = ./ruby;
          description = "Ruby development environment";
        };

        rust = {
          path = ./rust;
          description = "Rust development environment";
        };

        rust-toolchain = {
          path = ./rust-toolchain;
          description =
            "Rust development environment with Rust version defined by a rust-toolchain.toml file";
        };

        scala = {
          path = ./scala;
          description = "Scala development environment";
        };

        shell = {
          path = ./shell;
          description = "Shell script development environment";
        };

        snapcraft = {
          path = ./snapcraft;
          description = "Snapcraft development environment";
        };

        zig = {
          path = ./zig;
          description = "Zig development environment";
        };

        # Aliases
        rt = rust-toolchain;
      };
    };
}