diff --git a/Manifest.txt b/Manifest.txt
index 91bbe8977a90..321085d7f24c 100644
--- a/Manifest.txt
+++ b/Manifest.txt
@@ -48,6 +48,7 @@ lib/rubygems/commands/uninstall_command.rb
 lib/rubygems/commands/unpack_command.rb
 lib/rubygems/commands/update_command.rb
 lib/rubygems/commands/which_command.rb
+lib/rubygems/compatability.rb
 lib/rubygems/config_file.rb
 lib/rubygems/custom_require.rb
 lib/rubygems/defaults.rb
diff --git a/lib/rubygems.rb b/lib/rubygems.rb
index ea97a8743da5..2af1251eeea7 100644
--- a/lib/rubygems.rb
+++ b/lib/rubygems.rb
@@ -95,87 +95,20 @@
 #
 # -The RubyGems Team
 
-# Ruby 1.9.x has introduced some things that are awkward, and we need to
-# support them, so we define some constants to use later.
-module Gem
-  QUICKLOADER_SUCKAGE = RUBY_VERSION =~ /^1\.9\.1/
-  GEM_PRELUDE_SUCKAGE = RUBY_VERSION =~ /^1\.9\.2/
-end
-
-# Gem::QuickLoader exists in the gem prelude code in ruby 1.9.2 itself.
-# We gotta get rid of it if it's there, before we do anything else.
-# 
-# REFACTOR: Pulling this kind of thing out into some sort of file with
-# all of the hacks would be a Good Idea.
-if Gem::GEM_PRELUDE_SUCKAGE and defined?(Gem::QuickLoader) then
-  Gem::QuickLoader.remove
-
-  $LOADED_FEATURES.delete Gem::QuickLoader.path_to_full_rubygems_library
-
-  if $LOADED_FEATURES.any? do |path| path.end_with? '/rubygems.rb' end then
-    # TODO path does not exist here
-    raise LoadError, "another rubygems is already loaded from #{path}"
-  end
-
-  class << Gem
-    remove_method :try_activate if Gem.respond_to?(:try_activate, true)
-  end
-end
-
-require 'rubygems/defaults'
 require 'rbconfig'
-require "rubygems/deprecate"
-
 
 module Gem
   VERSION = '1.8.10'
-  DEFAULT_HOST = "https://rubygems.org"
-
-  ##
-  # Raised when RubyGems is unable to load or activate a gem.  Contains the
-  # name and version requirements of the gem that either conflicts with
-  # already activated gems or that RubyGems is otherwise unable to activate.
-
-  class LoadError < ::LoadError
-    # Name of gem
-    attr_accessor :name
-
-    # Version requirement of gem
-    attr_accessor :requirement
-  end
-  
-  # REFACTOR: Things like stopdoc tend to indicate that something might not
-  # be particularly well factored, and in this case, this is true. We're
-  # sort of patching over weirdness with RbConfig. This should be pulled
-  # out into some sort of file with all the compatibility hacks in it.
-  
-  # :stopdoc:
-
-  RubyGemsVersion = VERSION
-
-  RbConfigPriorities = %w[
-    EXEEXT RUBY_SO_NAME arch bindir datadir libdir ruby_install_name
-    ruby_version rubylibprefix sitedir sitelibdir vendordir vendorlibdir
-  ]
-
-  unless defined?(ConfigMap)
-    ##
-    # Configuration settings from ::RbConfig
-    ConfigMap = Hash.new do |cm, key|
-      cm[key] = RbConfig::CONFIG[key.to_s]
-    end
-  else
-    RbConfigPriorities.each do |key|
-      ConfigMap[key.to_sym] = RbConfig::CONFIG[key]
-    end
-  end
+end
 
-  RubyGemsPackageVersion = VERSION
+require 'rubygems/defaults'
+require 'rubygems/deprecate'
+require 'rubygems/compatability'
+require 'rubygems/errors'
 
+module Gem
   RUBYGEMS_DIR = File.dirname File.expand_path(__FILE__)
-
-  # :startdoc:
-
+  
   ##
   # An Array of Regexps that match windows ruby platforms.
 
diff --git a/lib/rubygems/compatability.rb b/lib/rubygems/compatability.rb
new file mode 100644
index 000000000000..4546fd81c74f
--- /dev/null
+++ b/lib/rubygems/compatability.rb
@@ -0,0 +1,50 @@
+# This file contains all sorts of little compatability hacks that we've
+# had to introduce over the years. Quarantining them into one file helps
+# us know when we can get rid of them.
+
+# Ruby 1.9.x has introduced some things that are awkward, and we need to
+# support them, so we define some constants to use later.
+module Gem
+  QUICKLOADER_SUCKAGE = RUBY_VERSION =~ /^1\.9\.1/
+  GEM_PRELUDE_SUCKAGE = RUBY_VERSION =~ /^1\.9\.2/
+end
+
+# Gem::QuickLoader exists in the gem prelude code in ruby 1.9.2 itself.
+# We gotta get rid of it if it's there, before we do anything else.
+if Gem::GEM_PRELUDE_SUCKAGE and defined?(Gem::QuickLoader) then
+  Gem::QuickLoader.remove
+
+  $LOADED_FEATURES.delete Gem::QuickLoader.path_to_full_rubygems_library
+
+  if $LOADED_FEATURES.any? do |path| path.end_with? '/rubygems.rb' end then
+    # TODO path does not exist here
+    raise LoadError, "another rubygems is already loaded from #{path}"
+  end
+
+  class << Gem
+    remove_method :try_activate if Gem.respond_to?(:try_activate, true)
+  end
+end
+
+module Gem
+  RubyGemsVersion = VERSION
+
+  RbConfigPriorities = %w[
+    EXEEXT RUBY_SO_NAME arch bindir datadir libdir ruby_install_name
+    ruby_version rubylibprefix sitedir sitelibdir vendordir vendorlibdir
+  ]
+
+  unless defined?(ConfigMap)
+    ##
+    # Configuration settings from ::RbConfig
+    ConfigMap = Hash.new do |cm, key|
+      cm[key] = RbConfig::CONFIG[key.to_s]
+    end
+  else
+    RbConfigPriorities.each do |key|
+      ConfigMap[key.to_sym] = RbConfig::CONFIG[key]
+    end
+  end
+
+  RubyGemsPackageVersion = VERSION
+end
diff --git a/lib/rubygems/defaults.rb b/lib/rubygems/defaults.rb
index e257c170adf1..993cd80f341c 100644
--- a/lib/rubygems/defaults.rb
+++ b/lib/rubygems/defaults.rb
@@ -1,6 +1,5 @@
 module Gem
-
-  # TODO: move this whole file back into rubygems.rb
+  DEFAULT_HOST = "https://rubygems.org"
 
   @post_install_hooks   ||= []
   @done_installing_hooks  ||= []
diff --git a/lib/rubygems/errors.rb b/lib/rubygems/errors.rb
index f2fe954adbe5..903e122b2ddd 100644
--- a/lib/rubygems/errors.rb
+++ b/lib/rubygems/errors.rb
@@ -1,36 +1,73 @@
-class Gem::ErrorReason; end # TODO: remove, unnecessary superclass
-
-# TODO move to lib/rubygems/platform_mismatch.rb
-# TODO write tests
-#--
-# Generated when a gem is found that isn't usable on the current platform.
+##
+# This file contains all the various exceptions and other errors that are used
+# inside of RubyGems.
 #
-class Gem::PlatformMismatch < Gem::ErrorReason
+# DOC: Confirm _all_
 
-  attr_reader :name
-  attr_reader :version
-  attr_reader :platforms
+module Gem
+  ##
+  # Raised when RubyGems is unable to load or activate a gem.  Contains the
+  # name and version requirements of the gem that either conflicts with
+  # already activated gems or that RubyGems is otherwise unable to activate.
 
-  def initialize(name, version)
-    @name = name
-    @version = version
-    @platforms = []
-  end
+  class LoadError < ::LoadError
+    # Name of gem
+    attr_accessor :name
 
-  def add_platform(platform)
-    @platforms << platform
+    # Version requirement of gem
+    attr_accessor :requirement
   end
 
-  #--
-  # Replace only "platforms", remove duplicate strings
-  def wordy
-    prefix = "Found #{@name} (#{@version})"
+  # FIX: does this need to exist? The subclass is the only other reference
+  # I can find.
+  class ErrorReason; end
+
+  # Generated when trying to lookup a gem to indicate that the gem
+  # was found, but that it isn't usable on the current platform.
+  #
+  # fetch and install read these and report them to the user to aid
+  # in figuring out why a gem couldn't be installed.
+  #
+  class PlatformMismatch < ErrorReason
+
+    ##
+    # the name of the gem
+    attr_reader :name
+
+    ##
+    # the version
+    attr_reader :version
+
+    ##
+    # The platforms that are mismatched
+    attr_reader :platforms
 
-    if @platforms.size == 1
-      "#{prefix}, but was for platform #{@platforms[0]}"
-    else
-      "#{prefix}, but was for platforms #{@platforms.join(' ,')}"
+    def initialize(name, version)
+      @name = name
+      @version = version
+      @platforms = []
+    end
+
+    ##
+    # append a platform to the list of mismatched platforms.
+    #
+    # Platforms are added via this instead of injected via the constructor
+    # so that we can loop over a list of mismatches and just add them rather
+    # than perform some kind of calculation mismatch summary before creation.
+    def add_platform(platform)
+      @platforms << platform
     end
-  end
 
+    ##
+    # A wordy description of the error.
+    def wordy
+      prefix = "Found #{@name} (#{@version})"
+
+      "Found %s (%), but was for platform%s %s" %
+        [@name,
+         @version,
+         @platforms.size == 1 ? 's' : '',
+         @platforms.join(' ,')]
+    end
+  end
 end
diff --git a/lib/rubygems/test_case.rb b/lib/rubygems/test_case.rb
index 02c34abc19ed..a37e9aa4735f 100644
--- a/lib/rubygems/test_case.rb
+++ b/lib/rubygems/test_case.rb
@@ -18,7 +18,7 @@
   gem 'json'
 end
 
-require "rubygems/deprecate"
+require 'rubygems/deprecate'
 require 'minitest/autorun'
 require 'fileutils'
 require 'tmpdir'