{
  description = "flake for OCaml dev";
  inputs = {
    nixpkgs.url = "github:NixOS/nixpkgs/release-24.11";
    nixpkgs-ocaml.url = "github:NixOS/nixpkgs/dd5621df6dcb90122b50da5ec31c411a0de3e538"; # OCaml 4.14.1
    systems.url = "github:nix-systems/default";
    flake-utils = {
      url = "github:numtide/flake-utils";
      inputs.systems.follows = "systems";
    };
  };

  outputs =
    { nixpkgs, nixpkgs-ocaml, flake-utils, ... }:
    flake-utils.lib.eachDefaultSystem (
      system:
      let
        pkgs = nixpkgs.legacyPackages.${system};
        ocaml-pkgs = nixpkgs-ocaml.legacyPackages.${system};
      in
      {
        devShells.default = pkgs.mkShell {
          packages = with pkgs; [
            gnumake
            dune_3
            ocaml-pkgs.ocaml
            ocaml-pkgs.ocamlPackages.utop
            ocaml-pkgs.ocamlPackages.findlib
            ocaml-pkgs.ocamlPackages.num
            ocaml-pkgs.ocamlPackages.menhir
            ocaml-pkgs.ocamlPackages.ocamlformat
            ocaml-pkgs.ocamlPackages.ocaml-lsp
          ];
        };
      }
    );
}