{
  description = "A flake to use a development version of Chicken.";

  inputs = {
    nixpkgs.url = "github:NixOS/nixpkgs/nixos-unstable";
    systems.url = "github:nix-systems/default";
  };

  outputs = inputs @ {
    self,
      nixpkgs,
      systems,
      ...
  }: let
    inherit (nixpkgs) lib;
    eachSystem = lib.genAttrs (import systems);
    pkgsFor = eachSystem (system:
      import nixpkgs {
        localSystem.system = system;
        overlays = with self.overlays; [chicken tcc-mob];
      });
  in {
    overlays = {
      default = self.overlays.chicken;

      tcc-mob = final: prev: {
        tcc-mob = final.callPackage ./nix/tinycc.nix {
          stdenv = final.gcc13Stdenv;
        };
      };
    };

    devShells = eachSystem (system: {
      default = let
        pkgs = import nixpkgs {
          overlays = [ self.overlays.tcc-mob ];
        };
      in pkgs.mkShell {
        packages = with pkgs; [ tcc-mob pkg-config ];
        shellHook = ''
          mkdir -p .chicken; cd .chicken
          curl https://code.call-cc.org/releases/5.4.0/chicken-5.4.0.tar.gz | tar xzf -
          cd ..
          make -C .chicken/chicken-5.4.0 -j16 PREFIX=$(pwd)/.chicken C_COMPILER=${pkgs.tcc-mob}/bin/tcc
          export CHICKEN_INSTALL_PREFIX="$(pwd)/.chicken"
          export CHICKEN_INSTALL_REPOSITORY="$(pwd)/.chicken/eggs"
          export CHICKEN_REPOSITORY_PATH="${pkgs.chicken}/lib/chicken/11:$CHICKEN_REPOSITORY_PATH:$(pwd)/.chicken/eggs"
          export PATH="$PATH:$CHICKEN_INSTALL_PREFIX/bin"
        '';
      };
    });
  };
}