anchor.diff:  
       cat > $out/bin/minecraft-server << EOF
       #!/bin/sh
  -    exec ${jre}/bin/java \$@ -jar $out/lib/minecraft/server.jar nogui
  +    exec ${jre_headless}/bin/java \$@ -jar $out/lib/minecraft/server.jar nogui
       EOF
   
       chmod +x $out/bin/minecraft-server
  
positive.code: 
    phases = "installPhase";
  
    meta = {
      description = "Minecraft Server";
      homepage    = "https://minecraft.net";
      license     = stdenv.lib.licenses.unfreeRedistributable;
      platforms   = stdenv.lib.platforms.unix;
      maintainers = with stdenv.lib.maintainers; [ thoughtpolice tomberek costrouc];
    };
  }
  
negative.code: { stdenv, fetchurl, jre_headless }:
  stdenv.mkDerivation {
    pname = "minecraft-server";
    version = "1.15.2";
  
    src = fetchurl {
      url =
        "https://launcher.mojang.com/v1/objects/bb2b6b1aefcd70dfd1892149ac3a215f6c636b07/server.jar";
      sha256 = "12kynrpxgcdg8x12wcvwkxka0fxgm5siqg8qq0nnmv0443f8dkw0";
    };
  
  