How can I compile my nixpkg on the NUR with a newer rustc version?

I’ve been attempting getting my waytrogen nixpkg to compile after it has has been published on the NUR but when I try to install the application on my nix flake it says that the rutc version needs to be 1.79 or greater but the one bundled with the rustPlatform is 1.76. I know that I can use oxalica/rust-overlay to use the latest stable rustc version but it requires me to import all of nixpkgs to work which is not allowed on the NUR. What can be done to update the compiler on the nixpkg?

{
  gtk4,
  glib,
  fetchFromGitHub,
  rustPlatform,
  lib,
  pkg-config,
  wrapGAppsHook4,
  ffmpeg,
  sqlite,
  openssl,
  gsettings-desktop-schemas
}:

rustPlatform.buildRustPackage rec {
  pname = "waytrogen";
  version = "0.5.5";
  preferLocalBuild = true;

  src = fetchFromGitHub {
    owner = "nikolaizombie1";
    repo = pname;
    rev = "cfedddbed9a957f5b1fe99af0e3bab0557ef1008";
    hash = "sha256-sDlxufSTXRyX+Cqs4CRUSITpN0IVRwlQTba+YsTWvi0=";
  };  

  nativeBuildInputs = [ pkg-config glib wrapGAppsHook4 sqlite ];
  buildInputs = [ glib gtk4 ffmpeg sqlite openssl gsettings-desktop-schemas ];
  env = {
    OPENSSL_NO_VENDOR = 1;
  };
  
  cargoHash = "sha256-/UVK0Jv36R0sKnMM+dzC0u/N7diK+8Es72sOMuO72nY=";

  postInstall = ''
  mkdir -p $out/share/glib-2.0/schemas && cp org.Waytrogen.Waytrogen.gschema.xml $out/share/glib-2.0/schemas/
  glib-compile-schemas $out/share/glib-2.0/schemas
  mkdir -p $out/share/locale/en/LC_MESSAGES && msgfmt locales/en/LC_MESSAGES/waytrogen.po -o waytrogen.mo && cp locales/en/LC_MESSAGES/waytrogen.mo $out/share/locale/en/LC_MESSAGES
  mkdir -p $out/share/locale/es/LC_MESSAGES && msgfmt locales/es/LC_MESSAGES/waytrogen.po -o waytrogen.mo && cp locales/es/LC_MESSAGES/waytrogen.mo $out/share/locale/es/LC_MESSAGES

  '';

  meta = {
    description = "A lightning fast wallpaper setter for Wayland.";
    longDescription = "A GUI wallpaper setter for Wayland that is a spiritual successor for the minimalistic wallpaper changer for X11 nitrogen. Written purely in the Rust 🦀 programming language. Supports hyprpaper, swaybg, mpvpaper and swww wallpaper changers.";
    homepage = "https://github.com/nikolaizombie1/waytrogen";
    license = lib.licenses.unlicense;
    maintainers = [ ];
  };
}

Are you building on an old release channel or something? rustc in 24.11 is currently 1.82 (1.83 on unstable).

Your reply gave me insight and I was able to figure out what it was. In my nix flake, I set the URL for the nur-packages repository I did not put to follow the nixpkgs repository so it was using an old version nixpkgs. The inputs of my nix flake ended up looking like this:

  inputs = {
    nixpkgs.url = "github:nixos/nixpkgs?ref=nixos-unstable";
    nikolaizombie1 = {
      url = "github:nikolaizombie1/nur-packages";
      inputs.nixpkgs.follows = "nixpkgs";
    };
  };