anchor.diff:          libPath = "lib/${versionNoPatch}";
           gemPath = "lib/${rubyEngine}/gems/${versionNoPatch}";
         };
  -    }; in self true;
  +    }
  +  ) args; in self;
   
   in {
     ruby_1_8_7 = generic {
  
positive.code: { stdenv, lib, fetchurl, fetchFromSavannah, fetchFromGitHub
  , zlib, zlibSupport ? true
  , openssl, opensslSupport ? true
  , gdbm, gdbmSupport ? true
  , ncurses, readline, cursesSupport ? true
  , groff, docSupport ? false
  , libyaml, yamlSupport ? true
  , libffi, fiddleSupport ? true
  , autoreconfHook, bison, autoconf
  , darwin ? null
  }:
  
  let
    op = stdenv.lib.optional;
  
negative.code:   opString = stdenv.lib.optionalString;
    patchSet = import ./rvm-patchsets.nix { inherit fetchFromGitHub; };
    config = import ./config.nix { inherit fetchFromSavannah; };
  
  generic = { majorVersion, minorVersion, teenyVersion, patchLevel, sha256 }: let
    versionNoPatch = "${majorVersion}.${minorVersion}.${teenyVersion}";
    version = "${versionNoPatch}-p${patchLevel}";
    fullVersionName = if patchLevel != "0" && stdenv.lib.versionOlder versionNoPatch "2.1"
      then version
      else versionNoPatch;
    tag = "v" + stdenv.lib.replaceChars ["." "p" "-"] ["_" "_" ""] fullVersionName;
    isRuby21 = majorVersion == "2" && minorVersion == "1";
    isRuby18 = majorVersion == "1" && minorVersion == "8";
    baseruby = self.override { useRailsExpress = false; };
    self = lib.makeOverridable (
      { stdenv, lib, fetchurl, fetchFromSavannah, fetchFromGitHub
      , useRailsExpress ? true
      , zlib, zlibSupport ? true
      , openssl, opensslSupport ? true
      , gdbm, gdbmSupport ? true
      , ncurses, readline, cursesSupport ? true
      , groff, docSupport ? false
      , libyaml, yamlSupport ? true
      , libffi, fiddleSupport ? true
      , autoreconfHook, bison, autoconf
      , darwin ? null
      }:
      stdenv.mkDerivation rec {
        inherit version;
  
        name = "ruby-${version}";
  
        src = if useRailsExpress then fetchFromGitHub {
          owner  = "ruby";
          repo   = "ruby";
          rev    = tag;
          sha256 = sha256.git;
        } else fetchurl {
          url = "http://cache.ruby-lang.org/pub/ruby/${majorVersion}.${minorVersion}/ruby-${fullVersionName}.tar.gz";
          sha256 = sha256.src;
        };
  
        # Have `configure' avoid `/usr/bin/nroff' in non-chroot builds.
  