let
  basicC = name: { stdenv }:
    stdenv.mkDerivation {
      inherit name;
      src = ./.;
      buildPhase = ''
        runHook preBuild
        gcc part2/${name}.c -o ${name}.bin
        runHook postBuild
      '';
      installPhase = ''
        runHook preInstall
        mkdir -p $out/bin
        install ${name}.bin $out/bin/${name}
        runHook postInstall
      '';
    };
in {
  a1-hello = basicC "hello";
  a1-employee = basicC "employee";
  a1-logwriter = basicC "logwriter";
}