diff --git a/pkgs/development/interpreters/ruby/fixes.nix b/pkgs/development/interpreters/ruby/fixes.nix
index eebda22263a..6457e713387 100644
--- a/pkgs/development/interpreters/ruby/fixes.nix
+++ b/pkgs/development/interpreters/ruby/fixes.nix
@@ -17,67 +17,51 @@
 # This seperates "what to build" (the exact gem versions) from "how to build"
 # (to make gems behave if necessary).
 
-{ lib, gemset, buildRubyGem, writeScript, ruby, libxml2, libxslt, python, stdenv
-, which, postgresql, v8_3_16_14, clang }:
+{ lib, fetchurl, writeScript, ruby, libxml2, libxslt, python, stdenv, which
+, postgresql, v8_3_16_14, clang }:
 
 let
-  const = x: y: x;
   v8 = v8_3_16_14;
 
-  gems = lib.mapAttrs (name: attrs:
-    if (lib.isDerivation attrs) then attrs
-    else (instantiate name attrs)
-  ) gemset;
+in
 
-  instantiate = (name: attrs:
-    let
-      gemPath = map (name: gems."${name}") (attrs.dependencies or []);
-      fixedAttrs = attrs // (fixes."${name}" or const {}) attrs;
-    in
-      buildRubyGem (fixedAttrs // { name = "${name}-${attrs.version}"; inherit gemPath; })
-  );
-
-  fixes = {
-    bundler = attrs: {
-      dontPatchShebangs = 1;
-    };
-
-    libv8 = attrs: {
-      buildFlags = [ "--with-system-v8" ];
-      buildInputs = [ which v8 python ];
-    };
-
-    nokogiri = attrs: {
-      buildFlags = [
-        "--with-xml2-dir=${libxml2}"
-        "--with-xml2-include=${libxml2}/include/libxml2"
-        "--with-xslt-dir=${libxslt}"
-        "--use-system-libraries"
-      ];
-    };
-
-    therubyracer = attrs: {
-      dontBuild = false;
-
-      preInstall = ''
-        addToSearchPath RUBYLIB "${gems.libv8}/gems/libv8-3.16.14.3/lib"
-        addToSearchPath RUBYLIB "${gems.libv8}/gems/libv8-3.16.14.3/ext"
-        ln -s ${clang}/bin/clang $TMPDIR/gcc
-        ln -s ${clang}/bin/clang++ $TMPDIR/g++
-        export PATH=$TMPDIR:$PATH
-      '';
-
-      postInstall = stdenv.lib.optionalString stdenv.isDarwin ''
-        cat >> $out/nix-support/setup-hook <<EOF
-          export DYLD_INSERT_LIBRARIES="$DYLD_INSERT_LIBRARIES''${!DYLD_INSERT_LIBRARIES:+:}${v8}/lib/libv8.dylib"
-        EOF
-      '';
-
-      buildFlags = [
-        "--with-v8-dir=${v8}" "--with-v8-include=${v8}/include"
-        "--with-v8-lib=${v8}/lib"
-      ];
-    };
+{
+  bundler = attrs: {
+    dontPatchShebangs = 1;
   };
 
-in gems
+  libv8 = attrs: {
+    buildFlags = [ "--with-system-v8" ];
+    buildInputs = [ which v8 python ];
+  };
+
+  nokogiri = attrs: {
+    buildFlags = [
+      "--with-xml2-dir=${libxml2}"
+      "--with-xml2-include=${libxml2}/include/libxml2"
+      "--with-xslt-dir=${libxslt}"
+      "--use-system-libraries"
+    ];
+  };
+
+  therubyracer = attrs: {
+    dontBuild = false;
+
+    preInstall = ''
+      ln -s ${clang}/bin/clang $TMPDIR/gcc
+      ln -s ${clang}/bin/clang++ $TMPDIR/g++
+      export PATH=$TMPDIR:$PATH
+    '';
+
+    postInstall = stdenv.lib.optionalString stdenv.isDarwin ''
+      cat >> $out/nix-support/setup-hook <<EOF
+        export DYLD_INSERT_LIBRARIES="$DYLD_INSERT_LIBRARIES''${!DYLD_INSERT_LIBRARIES:+:}${v8}/lib/libv8.dylib"
+      EOF
+    '';
+
+    buildFlags = [
+      "--with-v8-dir=${v8}" "--with-v8-include=${v8}/include"
+      "--with-v8-lib=${v8}/lib"
+    ];
+  };
+}
diff --git a/pkgs/development/interpreters/ruby/gem.nix b/pkgs/development/interpreters/ruby/gem.nix
index b136cb0de9b..85fa9d10cb5 100644
--- a/pkgs/development/interpreters/ruby/gem.nix
+++ b/pkgs/development/interpreters/ruby/gem.nix
@@ -3,7 +3,7 @@
 { name
 , namePrefix ? "${ruby.name}" + "-"
 , buildInputs ? []
-, doCheck ? false # TODO: fix this
+, doCheck ? false
 , dontBuild ? true
 , meta ? {}
 , gemPath ? []
diff --git a/pkgs/development/interpreters/ruby/import-gems.nix b/pkgs/development/interpreters/ruby/import-gems.nix
deleted file mode 100644
index 0efc7a7e2ee..00000000000
--- a/pkgs/development/interpreters/ruby/import-gems.nix
+++ /dev/null
@@ -1,57 +0,0 @@
-# is a pretty good interface for calling rubygems
-#
-# since there are so many rubygems, and we don't want to manage them all,
-# proposed design pattern is keep your gem dependencies in a local file
-# (hopefully managed with nix-bundle)
-#
-# use rubyLibs.importGems to call the local file, which has access to all
-# the stuff in here
-
-{ ruby, callPackage, pkgs }:
-
-let
-  buildRubyGem = callPackage ./gem.nix { inherit ruby; };
-  lib = ruby.stdenv.lib;
-
-  # A set of gems that everyone needs.
-  common = {
-    bundler = {
-      name = "bundler-1.6.5";
-      sha256 = "1s4x0f5by9xs2y24jk6krq5ky7ffkzmxgr4z1nhdykdmpsi2zd0l";
-    };
-
-    rake = {
-      name = "rake-10.3.2";
-      sha256 = "0nvpkjrpsk8xxnij2wd1cdn6arja9q11sxx4aq4fz18bc6fss15m";
-      dependencies = [ "bundler" ];
-    };
-  };
-
-  fixGems = gemset: callPackage ./fixes.nix { inherit buildRubyGem gemset ruby; };
-
-in
-
-(fixGems common) // {
-  inherit buildRubyGem;
-
-  # Import an attribute set of gems and apply a set of overrides. Nixpkgs fixes
-  # popular gems that don't behave. If you specify your own override for a gem,
-  # the one distributed with nixpgks will not be applied.
-  #
-  # Example:
-  #
-  #   importGems ./gems.nix (gemset: {
-  #     pg = buildRubyGem (gemset.pg // {
-  #       buildInputs = [ postgresql ];
-  #     });
-  #   });
-  importGems = file: gemOverrides:
-    let
-      # 1. Load set of gem names and versions from a bundix-created expression.
-      gemset = if (builtins.isAttrs file) then file else (callPackage file { });
-      # 2. Allow gems to be overriden by providing a derivation yourself.
-      config = gemset // (gemOverrides gemset);
-      # 3.
-      gems = fixGems config;
-    in gems;
-}
diff --git a/pkgs/development/interpreters/ruby/load-ruby-env.nix b/pkgs/development/interpreters/ruby/load-ruby-env.nix
index e2f61d82d8b..b73a9df9f83 100644
--- a/pkgs/development/interpreters/ruby/load-ruby-env.nix
+++ b/pkgs/development/interpreters/ruby/load-ruby-env.nix
@@ -1,51 +1,25 @@
-{rubyLibsWith, callPackage, lib, fetchurl, fetchgit}:
+{ pkgs, lib, callPackage, gemFixes }:
+
+{ gemset, ruby ? pkgs.ruby, fixes ? gemFixes }@args:
 
 let
+  const = x: y: x;
 
-  sourceInstantiators = {
-    # Many ruby people use `git ls-files` to compose their gemspecs.
-    git = (attrs: fetchgit { inherit (attrs) url rev sha256 leaveDotGit; });
-    url = (attrs: fetchurl { inherit (attrs) url sha256; });
-  };
+  buildRubyGem = callPackage ./gem.nix { inherit ruby; };
 
-in
-
-{
-  # Loads a set containing a ruby environment definition. The set's `gemset`
-  # key is expected to contain a set of gems. A gemset definition looks like this:
-  #
-  #  {
-  #    gemset = {
-  #      rack-test = {
-  #        version = "0.6.2";
-  #        src = {
-  #          type = "url";
-  #          url = "https://rubygems.org/downloads/rack-test-0.6.2.gem";
-  #          sha256 = "01mk715ab5qnqf6va8k3hjsvsmplrfqpz6g58qw4m3l8mim0p4ky";
-  #        };
-  #        dependencies = [ "rack" ];
-  #      };
-  #    };
-  #  }
-  loadRubyEnv = expr: config:
+  instantiate = (name: attrs:
     let
-      expr' =
-        if builtins.isAttrs expr
-        then expr
-        else import expr;
-      gemset = lib.mapAttrs (name: attrs:
-        attrs // {
-          src = (sourceInstantiators."${attrs.src.type}") attrs.src;
-          dontBuild = !(attrs.src.type == "git");
-        }
-      ) expr'.gemset;
-      ruby = config.ruby;
-      rubyLibs = rubyLibsWith ruby;
-      gems = rubyLibs.importGems gemset (config.gemOverrides or (gemset: {}));
-      gemPath = map (drv: "${drv}") (
-        builtins.filter lib.isDerivation (lib.attrValues gems)
-      );
-    in {
-      inherit ruby gems gemPath;
-    };
-}
+      gemPath = map (name: gemset''."${name}") (attrs.dependencies or []);
+      fixedAttrs = attrs // (fixes."${name}" or (const {})) attrs;
+    in
+      buildRubyGem (fixedAttrs // { name = "${name}-${attrs.version}"; inherit gemPath; })
+  );
+
+  gemset' = if builtins.isAttrs gemset then gemset else callPackage gemset { };
+
+  gemset'' = lib.flip lib.mapAttrs gemset' (name: attrs:
+    if (lib.isDerivation attrs) then attrs
+    else (instantiate name attrs)
+  );
+
+in gemset''
diff --git a/pkgs/development/interpreters/ruby/rubygems.nix b/pkgs/development/interpreters/ruby/rubygems.nix
index b8fe56c1a10..d6bc8b1daf2 100644
--- a/pkgs/development/interpreters/ruby/rubygems.nix
+++ b/pkgs/development/interpreters/ruby/rubygems.nix
@@ -1,6 +1,7 @@
 args : with args; 
 rec {
 
+  name = "rubygems-" + version;
   version = "2.4.1";
   src = fetchurl {
     url = "http://production.cf.rubygems.org/rubygems/${name}.tgz";
@@ -23,7 +24,6 @@ rec {
   /* doConfigure should be specified separately */
   phaseNames = ["doPatch" "doInstall"];
       
-  name = "rubygems-" + version;
   meta = {
     description = "Ruby gems package collection";
     longDescription = ''
diff --git a/pkgs/top-level/all-packages.nix b/pkgs/top-level/all-packages.nix
index 3a80854850a..515424a4068 100644
--- a/pkgs/top-level/all-packages.nix
+++ b/pkgs/top-level/all-packages.nix
@@ -4030,6 +4030,8 @@ let
     wrapPython = pythonPackages.wrapPython;
   };
 
+  gemFixes = callPackage ../development/interpreters/ruby/fixes.nix { };
+
   ruby_1_8_7 = callPackage ../development/interpreters/ruby/ruby-1.8.7.nix { };
   ruby_1_9_3 = callPackage ../development/interpreters/ruby/ruby-1.9.3.nix { };
   ruby_2_0_0 = lowPrio (callPackage ../development/interpreters/ruby/ruby-2.0.0.nix { });
@@ -4045,23 +4047,9 @@ let
   ruby_2_0 = ruby_2_0_0;
   ruby_2_1 = ruby_2_1_3;
 
-  rubyLibsWith = ruby: callPackage ../development/interpreters/ruby/import-gems.nix {
-    inherit ruby;
-  };
+  loadRubyEnv = callPackage ../development/interpreters/ruby/load-ruby-env.nix { };
 
-  loadRubyEnv = (callPackage ../development/interpreters/ruby/load-ruby-env.nix { }).loadRubyEnv;
-
-  rubyLibs_1_8_7 = rubyLibsWith ruby_1_8_7;
-  rubyLibs_1_9_3 = rubyLibsWith ruby_1_9_3;
-  rubyLibs_2_0_0 = rubyLibsWith ruby_2_0_0;
-  rubyLibs_2_1_0 = rubyLibsWith ruby_2_1_0;
-  rubyLibs_2_1_1 = rubyLibsWith ruby_2_1_1;
-  rubyLibs_2_1_2 = rubyLibsWith ruby_2_1_2;
-  rubyLibs_2_1_3 = rubyLibsWith ruby_2_1_3;
-
-  rubyLibs = recurseIntoAttrs rubyLibs_1_9_3;
-
-  rake = rubyLibs.rake;
+  rake = ... # TODO
 
   rubySqlite3 = callPackage ../development/ruby-modules/sqlite3 { };