How to produce a package with a newer source code version?

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1

Hi there

Pretty new user of Nixos here. No developer, just a user :slight_smile:

If I would like to test a newer version of a package, how would I need to do that? Do I understand it correctly that an overlay is needed?

I am interested in the fprintd package (NixOS Search), which is currently at version 1.94.5 in unstable. But I need the latest version 1.94.9.

Would I need to add such an overlay to my config?

nixpkgs.overlays = [ (self: super: {
        fprintd = super.fprintd.overrideAttrs (old: {
            finalAttrs.version = "1.94.9";
            src.hash = "sha256-..........";
          });
    }) ];

I am not sure, if that references the attributes correctly. And the hash I would need to calculate myself before and replace it with the calculated value, I guess?

Thanks for any support.

Michael

1 Like
2

This should be version = "1.94.9";

No, set it to the empty string, rebuild, error tells you the hash.
And setting src.hash won’t do anything, you really need to set something like

  src = old.src.override {
    hash = "";
  };

or

  src = old.src.overrideAttrs {
    outputHash = "";
  };

instead of src.hash.

Not necessarily, depends on how you’re using it. If you’re using some nixos module, there’s usually a .package option you can set instead. (If there isn’t one, then sure, use an overlay.)

2 Likes
3

Thanks for your support.
I got a few steps further. Apparently the systems even starts building the fprintd in version 1.94.9, but , unfortunately, the nixos package tries to apply a patch, which no longer applies cleanly. The current version is built on 1.94.5, which is about a year old.
So, I need to see what changes are needed to the patch file and then try to also replace the patch file with a custom one.