Can't get GNOME shell applet to work, even with gtk4 support apparently enabled

[jjramsey]

I'm trying to get an Nix overlay for the Workrave 1.10.53 Nix package to work, and I'm stumped. I have --enable-gnome45 as a configure flags, and gtk4 as a build input, and near as I can tell, Workrave is being compiled with that flag and with GTK4 support. The file "Workrave-2.0.typelib" is even in /run/current-system/sw/lib/girepository-1.0, and the file "Workrave-2.0.gir" is in /run/current-system/sw/share/gir-1.0 (where, as far as I can tell, /run/current-system/sw might as well be /usr).

Yet in the extension manager, I still see this error message:

Error: Requiring Workrave 2.0: Typelib file for namespace 'Workrave' version '2.0' not found

Any idea what's going on here? What am I missing for the Workrave build?

BTW, for those who know NixOS, this is what my overlay currently looks like:

  nixpkgs.overlays = [
    (final: prev: {
      workrave = prev.workrave.overrideAttrs (
        finalAttrs: prevAttrs: {
          configureFlags = # prevAttrs.configureFlags ++
            [ "--enable-gnome45" ];
          buildInputs = prevAttrs.buildInputs ++ [ pkgs.gtk4 ];
        }
      );
    })
  ];

[jjramsey]

Looks like the answer is mainly here: NixOS/nixpkgs#420671