Dunno...

  buildPackages' = buildPackages.extend (self: super: {nodejs = nodejs_23;});
  buildNpmPackage23 = buildNpmPackage.override {
    buildPackages = buildPackages';
  };

Ended up with something like this and this seemed to work. There are probably better ways to do this 🤷

bmod> [11ty] Writing /nix/store/n1ki5hpv6qjn517cgw10ssl86bfmm753-bmod-static/servers/index.html from ./_root/servers.html (liquid)
bmod> [11ty] Writing /nix/store/8yzd73k47j7fjsx5f0igxssp282ib0b6-bmod-static/balance/index.html from ./_root/balance.html (liquid)
bmod> [11ty] Writing /nix/store/n7kjqr06ybdqbaqjyihkn4dhzkprgaaf-bmod-static/moddedweapons/index.html from ./_root/moddedweapons.html (liquid)
bmod> [11ty] Writing /nix/store/n7kjqr06ybdqbaqjyihkn4dhzkprgaaf-bmod-static/balance/index.html from ./_root/balance.html (liquid)
bmod> [11ty] Writing /nix/store/n7kjqr06ybdqbaqjyihkn4dhzkprgaaf-bmod-static/asset-pack-test/index.html from ./_root/asset-pack-test.html (liquid)
bmod> /nix/store/21h54w4z8q9k7vjp11kl4xglbh8sfy5f-npm-build-hook/nix-support/setup-hook: line 3:   278 Killed                  npm run ${npmWorkspace+--workspace=$npmWorkspace} "$npmBuildScript" $npmBuildFlags "${npmBuildFlagsArray[@]}" $npmFlags "${npmFlagsArray[@]}"
bmod> ERROR: `npm build` failed
bmod> Here are a few things you can try, depending on the error:
bmod> 1. Make sure your build script (static:build) exists
bmod>   If there is none, set `dontNpmBuild = true`.
bmod> 2. If the error being thrown is something similar to "error:0308010C:digital envelope routines::unsupported", add `NODE_OPTIONS = "--openssl-legacy-provider"` to your derivation
bmod>   See https://github.com/webpack/webpack/issues/14532 for more information.
error: builder for '/nix/store/n2548zdlw6hjfgnkxq9is6x3n9kc2qmv-bmod.drv' failed with exit code 1
error: 1 dependencies of derivation '/nix/store/x1bxxf20ncsby1v5y0jadsjs1bvbdpy2-Caddyfile.drv' failed to build
error: 1 dependencies of derivation '/nix/store/bk0lhrw88ldg2vx04pbbfv9wvp5mnwx1-Caddyfile-formatted.drv' failed to build
error: 1 dependencies of derivation '/nix/store/53xm62vz6cq07wqkakf670vhz5s2rsjd-etc.drv' failed to build
error: 1 dependencies of derivation '/nix/store/gxndj1l21fa3pvq86b2ghlqh05km3c0b-nixos-system-blutsauger-25.11.20250624.30a61f0.drv' failed to build
Command '['nix', '--extra-experimental-features', 'nix-command flakes', 'build', '--print-out-paths', 'gitlab:balancemod/main-site-nixos#nixosConfigurations."blutsauger".config.system.build.toplevel', '--print-build-logs', '--show-trace', '--refresh', '--no-link']' returned non-zero exit status 1.

[tumble@blutsauger:~]$