Electron rebuilds completely with every update

Help
1

I’m using some electron based apps on nixos-unstable and electron-unwrapped is recompiled withe every update. I’m having this problem with heroic games launcher, bitwarden-desktop, signal-desktop, and deltachat-desktop. Every update does the long and resource-intensive recompilation of multiple electron-unwrapped versions. Are they not built for the main binary cache?

2

Do you by any chance set a nix version other than nixStable in an overlay in your config?

I used to do this to work around a bug in the nix executable at the time, and it started to trigger electron rebuilds. I think it happened via a dependency on nix in pkgs/build-support/node/fetch-npm-deps/default.nix and I fixed it for a while, but the fix itself broke at some point. But as nix was fixed as well at that time I just dropped the overlay completely and I don’t have an up-to-date workaround.

3

Because I trigged my own curiosity - electron now also depends on fetch-yarn-deps so my workaround was no longer sufficient. This now seems to work though:

  overlay-nixVersion = final: prev: {
    nix = final.nixUnstable;

    # Prevent extensive rebuild of electron
    inherit (final.callPackages "${inputs.nixpkgs}/pkgs/build-support/node/fetch-npm-deps" { nix = final.nixStable; })
      fetchNpmDeps prefetch-npm-deps;
    inherit (final.callPackages "${inputs.nixpkgs}/pkgs/build-support/node/fetch-yarn-deps" { nix = final.nixStable; })
      fetchYarnDeps prefetch-yarn-deps;
    inherit (final.callPackages "${inputs.nixpkgs}/pkgs/tools/package-management/nix-prefetch-scripts" { nix = final.nixStable; })
      nix-prefetch-git;  # more prefetch scripts exist and depend on nix
  };

Of course if you were not using an overlay for nix in the first place this is all useless to you, but maybe someone else will find it useful.

4

What are your overlays and do you allow any insecure packages?

6

Yes, that could be it. Thank you. I used the unstable NIx version because of an error a while ago.

7

It seems to be a problem with the Nix unstable overlay.