{ nixpkgs ? import {} }: let haskellPackages = nixpkgs.haskellPackages.override { overrides = self: super: { hip = import ./hip.nix { inherit nixpkgs; }; }; }; perceptual-hash = haskellPackages.callCabal2nix "perceptual-hash" (nixpkgs.fetchFromGitHub { owner = "vmchale"; repo = "phash"; rev = "90fa59bec93b6adcad614d37033c1f2e059b6e46"; sha256 = "sha256-CysvgcgzIuvKFEwNnCYHB6MXGzQnBQN7Nuo6HADuavk="; }) {}; in perceptual-hash