{ stdenv, fetchurl }: let fetch = { version, src ? builtins.getAttr stdenv.system sources, sources ? null }: { inherit version src; }; in { v10_0_2 = fetch { version = "10.0.2"; src = fetchurl{ url = "http://geant4.cern.ch/support/source/geant4.10.00.p02.tar.gz"; sha256 = "9d615200901f1a5760970e8f5970625ea146253e4f7c5ad9df2a9cf84549e848"; }; }; }