{
  pkgs,
  lib,
  config,
  inputs,
  ...
}: let
  opkgs = import inputs.ocaml {system = pkgs.system;};

  murmur = opkgs.ocamlPackages.buildDunePackage {
    pname = "murmur3";
    version = "0.4";
    src = pkgs.fetchFromGitHub {
      owner = "polwex";
      repo = "ocaml-murmur3";
      rev = "be8ef049b515ccc1adc7393975e0f4a12a95dcb0";
      sha256 = "oojBUIo8YIzVxAau4jwToYinemuDKYwaX+2OaZ28mW0=";
    };
  };
in {
  # nixConfig = {
  #   extra-substituters = "https://anmonteiro.nix-cache.workers.dev";
  #   extra-trusted-public-keys = "ocaml.nix-cache.com-1:/xI2h2+56rwFfKyyFVbkJSeGqSIYMC/Je+7XXqGKDIY=";
  # };

  # https://devenv.sh/basics/
  env.GREET = "devenv";
  #rust
  env.LIBCLANG_PATH = pkgs.lib.makeLibraryPath [pkgs.llvmPackages_latest.libclang.lib];
  #ocaml
  # overlays = [
  # inputs.ocaml.overlays.default
  # (final: prev: {
  #   ocamlPackages = prev.ocaml-ng.ocamlPackages_5_3;
  #   ocaml = prev.ocaml-ng.ocamlPackages_5_3.ocaml;
  # })
  # ];

  # https://devenv.sh/packages/
  packages = with pkgs;
    [
      git
      #rust
      openssl
      pkg-config
      clang
      zig_0_14
      opkgs.ocamlPackages.lmdb
      (python312.withPackages (py: [py.requests]))
    ]
    ++ (with opkgs.ocamlPackages; [
      ocaml
      dune_3
      opam
      findlib
      merlin
      utop
      odoc
      ocaml-lsp
      ocp-indent
      ocamlformat
      #
      #
      cmdliner
      logs
      zarith
      cmdliner
      logs
      eio_main
      lmdb
      domainslib
      piaf
      murmur
      ctypes
      ctypes-foreign
      # testing

      alcotest
      qcheck
      qcheck-alcotest
      landmarks
    ]);

  # https://devenv.sh/languages/
  languages.rust.enable = true;
  # languages.ocaml = {
  #   enable = true;
  # };

  # https://devenv.sh/processes/
  # processes.dev.exec = "${lib.getExe pkgs.watchexec} -n -- ls -la";

  # https://devenv.sh/services/
  # services.postgres.enable = true;

  # https://devenv.sh/scripts/
  scripts.hello.exec = ''
    echo hello from $GREET
  '';

  # https://devenv.sh/basics/
  enterShell = ''
    hello         # Run scripts directly
    git --version # Use packages
  '';

  # https://devenv.sh/tasks/
  # tasks = {
  #   "myproj:setup".exec = "mytool build";
  #   "devenv:enterShell".after = [ "myproj:setup" ];
  # };

  # https://devenv.sh/tests/
  enterTest = ''
    echo "Running tests"
    git --version | grep --color=auto "${pkgs.git.version}"
  '';

  # https://devenv.sh/git-hooks/
  # git-hooks.hooks.shellcheck.enable = true;

  # See full reference at https://devenv.sh/reference/options/
}