Hey guys!

Does anybody know how to create a package for a yarn project that uses pnp?

I'm trying to package Verdaccio https://github.com/NixOS/nixpkgs/pull/398441

but it seems that pnp is not supported by the current packaging tooling

Yes I followed the docs, and it doesn't work because fetchYarnDeps only supports yarn v1 (they have # yarn lockfile v1 as first line, which yarn berry doesn't have)

Funny enough, going the nodePackages at least allows me to build and run the package correctly, but it breaks the pipeline because generate script pulls in python for some reason

Yes I followed the docs, and it doesn't work because fetchYarnDeps only supports yarn v1 (they have # yarn lockfile v1 as first line, which yarn berry doesn't have)

Funny enough, going the nodePackages at least allows me to build and run the package correctly, but it breaks the pipeline because generate script pulls in python2 for some reason

Hmm, the actual fetcher seems to work fine manually for me.
e.g. this works correctly:

{
  stdenv,
  fetchFromGitHub,
  yarn-berry_3,
  nodejs,
}:

stdenv.mkDerivation (finalAttrs: {
  pname = "verdaccio";
  version = "6.1.2";

  src = fetchFromGitHub {
    owner = "verdaccio";
    repo = "verdaccio";
    rev = "v${finalAttrs.version}";
    hash = "sha256-EssvN5HtGI5Hmw4EXetj5nzrkBZAAJGgOx09dlYJzhI=";
  };

  nativeBuildInputs = [
    yarn-berry_3.yarnBerryConfigHook
    yarn-berry_3
    nodejs
  ];

  offlineCache = yarn-berry_3.fetchYarnBerryDeps {
    inherit (finalAttrs) src;
    hash = "sha256-jzkmDxQtIFMa1LIPcvKKsXIItPntgXTavoWhd5eZWyQ=";
  };

  buildPhase = ''
    yarn build
  '';

  installPhase = ''
    mkdir -p $out
    cp -r build $out
  '';
})