In reply to @hexa:lossy.network
that is precisely the issue with fonts, reminds me of #staging:nixos.org a while ago 😄

I did generate yarn.lock with yarn install but now I have next obstacle: when I try to use fetchYarnDeps with it, it gives me following error:

> Error: The lockfile entry with key "@janhq/core@link:./electron/core" cannot be downloaded because it is missing the "resolved" attribute, which should contain the URL to download from. The lockfile might be invalid.

I did generate yarn.lock with yarn install but now I have next obstacle: when I try to use fetchYarnDeps with it, it gives me following error:

`

Error: The lockfile entry with key "@janhq/core@link:./electron/core" cannot be downloaded because it is missing the "resolved" attribute, which should contain the URL to download from. The lockfile might be invalid.
`

I did generate yarn.lock with yarn install but now I have next obstacle: when I try to use fetchYarnDeps with it, it gives me following error:

Error: The lockfile entry with key "@janhq/core@link:./electron/core" cannot be downloaded because it is missing the "resolved" attribute, which should contain the URL to download from. The lockfile might be invalid.

{ lib
, stdenv
, fetchFromGitHub
, fetchYarnDeps
, yarn2nix
, yarn
}:

stdenv.mkDerivation rec {
  pname = "jan";
  version = "0.5.2";

  src = fetchFromGitHub {
    owner = "janhq";
    repo = pname;
    rev = "v${version}";
    hash = "sha256-MByI66+fmHQOMMlpA/uJ9/iL8ImAr7XbzW4Hht7CeDM=";
  };

  offlineCache = fetchYarnDeps {
    yarnLock = ./yarn.lock;
    sha256 = lib.fakeSha256;
  };

  nativeBuildInputs = [
    yarn2nix
    yarn
  ];

  buildPhase = ''
    cd joi
    yarn2nix
    yarn build
  '';

  meta = {
    homepage = "https://jan.ai";
    license = lib.licenses.gpl3Only;
  };

}