self: super:
let
  # unstable = import <nixos-unstable> {};
  unstable = import (fetchTarball {
    url = "https://github.com/NixOS/nixpkgs/archive/fc2c606a7ac8fb48be4181f777d029bd75c0c58a.tar.gz";
    sha256 = "1sd4587ip0fc05nwbaiiqqfx5ra2iyjdcmrapda4g41m0c9cyd34";
   }) {};
in
{
  jackett = unstable.jackett;
}