nixpkgslib: let
  lib = nixpkgslib // nlib;

  nlib = with builtins;
  with lib; {
    # Generic power of number
    pow = base: e:
      if e == 0
      then 1
      else foldl (x: _: x * base) 1 (genList id (e - 1));
    # Power of 2
    pow2 = pow 2;

    # Convert integer to list of bits
    int2bits = len: e: reverseList (genList (x: bitAnd e (pow2 (x + 1)) > 0) len);
    # Reverse operation for int2bits
    bits2int = l: let
      len = length l;
      zf = a: b:
        if a
        then pow2 b
        else 0;
    in
      foldl add 0 (zipListsWith zf l (genList (i: len - i) len));

    # IPv4 utilities
    ipv4 = import ./ipv4.nix lib;
  };
in
  nlib