diff --git a/Rakefile b/Rakefile
index 1040ca8..c796d16 100644
--- a/Rakefile
+++ b/Rakefile
@@ -1,22 +1,6 @@
 require 'bundler'
 Bundler::GemHelper.install_tasks
 
-begin
-  require 'rspec/core/rake_task'
-
-  RSpec::Core::RakeTask.new(:spec)
-rescue LoadError
-  "#$! - no rspec"
-end
-
-begin
-  require 'rspec/core/rake_task'
-
-  RSpec::Core::RakeTask.new(:spec)
-rescue LoadError
-  "#$! - no rspec"
-end
-
 begin
   require 'cucumber'
   require 'cucumber/rake/task'
@@ -28,5 +12,5 @@ rescue LoadError
   "#$! - no cucumber"
 end
 
-task :default => [ :spec, :cucumber ]
+task :default => [ :cucumber ]
 
diff --git a/features/cli.feature b/features/cli.feature
index c3eaa1b..ee0d17d 100644
--- a/features/cli.feature
+++ b/features/cli.feature
@@ -1,6 +1,6 @@
 Feature: CLI
   Scenario: Switch back to the original pre-deployment environment
-    Given I have the file "tmp/Gemfile.erb" with the content:
+    Given I have the file "tmp/Gemfile.penchant" with the content:
       """
       gem 'rake'
       """
@@ -12,7 +12,7 @@ Feature: CLI
     Then the file "tmp/Gemfile" should have the following content:
       """
       # generated by penchant, environment: local
-      gem 'rake'
+      gem "rake"
       """
       And the output should include "fallback: other"
 
diff --git a/features/gemfile.feature b/features/gemfile.feature
deleted file mode 100644
index 35a43eb..0000000
--- a/features/gemfile.feature
+++ /dev/null
@@ -1,123 +0,0 @@
-@fakefs
-Feature: Gemfiles
-  Scenario: When rebuilding for deployment, save the original state
-    Given I have the file "Gemfile.erb" with the content:
-      """
-      this is content
-      """
-      And I have the file "Gemfile" with the content:
-      """
-      # generated by penchant, environment: local
-      """
-    When I rebuild the Gemfile for "production" mode with deployment
-    Then the file "Gemfile" should have the following content:
-      """
-      # generated by penchant, environment: production, deployment mode (was local)
-      this is content
-      """
-
-  Scenario: When unbundling from deployment with an original state, switch to that state
-    Given I have the file "Gemfile.erb" with the content:
-      """
-      this is content
-      """
-      And I have the file "Gemfile" with the content:
-      """
-      # generated by penchant, environment: production, deployment mode (was local)
-      """
-    When I rebuild the Gemfile asking to switch back to the previous state
-    Then the file "Gemfile" should have the following content:
-      """
-      # generated by penchant, environment: local
-      this is content
-      """
-
-  Scenario: Simple env
-    Given I have the file "Gemfile.erb" with the content:
-      """
-      gem 'test'
-      <% env :local do %>
-        gem 'test'
-      <% end %>
-      """
-    When I rebuild the Gemfile for "local" mode
-    Then the file "Gemfile" should have the following stripped content:
-      """
-      # generated by penchant, environment: local
-      gem 'test'
-      gem 'test'
-      """
-
-  Scenario: Use placeholder expansion
-    Given I have the file "Gemfile.erb" with the content:
-      """
-      <% env :local, :path => '../%s' do %>
-        gem 'test'
-      <% end %>
-      """
-    When I rebuild the Gemfile for "local" mode
-
-    Then the file "Gemfile" should have the following stripped content:
-      """
-      # generated by penchant, environment: local
-      gem 'test', {:path=>"../test"}
-      """
-
-  Scenario: Use a gem list for an operation
-    Given I have the file "Gemfile.erb" with the content:
-      """
-      <% gems 'test' do %>
-        <% env :local, :path => '../%s' do %>
-          <%= gem %>
-        <% end %>
-      <% end %>
-      """
-    When I rebuild the Gemfile for "local" mode
-    Then the file "Gemfile" should have the following stripped content:
-      """
-      # generated by penchant, environment: local
-      gem 'test', {:path=>"../test"}
-      """
-  
-  Scenario: Let gem get additional info
-    Given I have the file "Gemfile.erb" with the content:
-      """
-      <% gems 'test' do %>
-        <%= gem :path => '../%s' %>
-      <% end %>
-      """
-    When I rebuild the Gemfile for "local" mode
-    Then the file "Gemfile" should have the following content:
-      """
-      # generated by penchant, environment: local
-
-        gem 'test', {:path=>"../test"}
-
-      """
-  
-  Scenario: Use a gem list without a block
-    Given I have the file "Gemfile.erb" with the content:
-      """
-      <% gems 'test', :path => '../%s' %>
-      """
-    When I rebuild the Gemfile for "local" mode
-    Then the file "Gemfile" should have the following content:
-      """
-      # generated by penchant, environment: local
-      gem 'test', {:path=>"../test"}
-
-      """
-
-  Scenario: Use a gem list with an array
-    Given I have the file "Gemfile.erb" with the content:
-      """
-      <% gems [ 'test' ], :path => '../%s' %>
-      """
-    When I rebuild the Gemfile for "local" mode
-    Then the file "Gemfile" should have the following content:
-      """
-      # generated by penchant, environment: local
-      gem 'test', {:path=>"../test"}
-
-      """
-
diff --git a/lib/penchant/gemfile.rb b/lib/penchant/gemfile.rb
index ead4c1c..b44494c 100644
--- a/lib/penchant/gemfile.rb
+++ b/lib/penchant/gemfile.rb
@@ -292,60 +292,6 @@ module Penchant
       end
     end
 
-    class ERBFile < FileProcessor
-      def handle_result(data)
-        $stderr.puts "ERB files are deprecated. Please convert them to the Ruby format."
-
-        @output << ERB.new(data, nil, nil, '@_erbout').result(binding)
-      end
-
-      def env(check, template = {}, &block)
-        if check.to_s == @environment.to_s
-          original_erbout = @_erbout.dup
-          @_erbout = ''
-
-          output = instance_eval(&block).lines.to_a
-
-          output.each do |line|
-            if gem_name = line[%r{gem ['"]([^'"]+)['"]}, 1]
-              new_line = line.rstrip
-
-              if !(options = process_options(gem_name, template)).empty?
-                new_line += ", #{options.inspect}"
-              end
-
-              line.replace(new_line + "\n")
-            end
-          end
-
-          @_erbout = original_erbout + output.join
-        end
-      end
-
-      def gems(*gems)
-        template = {}
-        template = gems.pop if gems.last.instance_of?(Hash)
-
-        gems.flatten.each do |gem|
-          @_current_gem = gem
-          if block_given?
-            yield
-          else
-            @_erbout += gem(template) + "\n"
-          end
-        end
-      end
-
-      def gem(template = {})
-        output = "gem '#{@_current_gem}'" 
-        options = process_options(@_current_gem, template)
-        if !options.empty?
-          output += ", #{options.inspect}"
-        end
-        output
-      end
-    end
-
     class PenchantFile < FileProcessor
       def handle_result(data)
         instance_eval(data)
@@ -456,16 +402,7 @@ module Penchant
     end
 
     def builder
-      return @builder if @builder
-
-      klass = case File.extname(processable_gemfile_path)
-      when '.penchant'
-        PenchantFile
-      when '.erb'
-        ERBFile
-      end
-
-      @builder = klass.new(template)
+      @builder ||= PenchantFile.new(template)
     end
 
     def template
diff --git a/spec/lib/penchant/dot_penchant_spec.rb b/spec/lib/penchant/dot_penchant_spec.rb
deleted file mode 100644
index 8be4d9e..0000000
--- a/spec/lib/penchant/dot_penchant_spec.rb
+++ /dev/null
@@ -1,45 +0,0 @@
-require 'spec_helper'
-
-describe Penchant::DotPenchant do
-  include FakeFS::SpecHelpers
-
-  describe '.run' do
-    before do
-      File.open('.penchant', 'wb') { |fh|
-        fh.puts "@did_run = env"
-      }
-    end
-
-    it 'should run the file in the environment' do
-      dot_file = Penchant::DotPenchant.run(:this)
-
-      dot_file.instance_variable_get(:@did_run).should == :this
-    end
-  end
-
-  let(:dot_file) { described_class.new }
-
-  describe '#rake' do
-    context 'without Gemfile' do
-      before do
-        Kernel.expects(:system).with('rake task1 task2')
-      end
-
-      it 'should run the rake task via system' do
-        dot_file.rake("task1", "task2")
-      end
-    end
-
-    context 'with Gemfile' do
-      before do
-        File.open('Gemfile', 'wb')
-        Kernel.expects(:system).with('bundle exec rake task1 task2')
-      end
-
-      it 'should run the rake task via system' do
-        dot_file.rake("task1", "task2")
-      end
-    end
-  end
-end
-
diff --git a/spec/lib/penchant/gemfile_spec.rb b/spec/lib/penchant/gemfile_spec.rb
deleted file mode 100644
index 381985e..0000000
--- a/spec/lib/penchant/gemfile_spec.rb
+++ /dev/null
@@ -1,296 +0,0 @@
-require 'spec_helper'
-
-describe Penchant::Gemfile do
-  include FakeFS::SpecHelpers
-
-  let(:dir) { File.expand_path(Dir.pwd) }
-  let(:gemfile) { described_class.new(dir) }
-
-  let(:gemfile_path) { File.join(dir, 'Gemfile') }
-  let(:gemfile_erb_path) { File.join(dir, 'Gemfile.erb') }
-
-  def write_file(path, content = nil)
-    FileUtils.mkdir_p(File.dirname(path))
-
-    File.open(path, 'wb') do |fh|
-      content = yield if block_given?
-      fh.print content
-    end
-  end
-
-  subject { gemfile }
-
-  context 'with no gemfile' do
-    it { should_not have_gemfile }
-    it { should_not have_gemfile_erb }
-  end
-
-  context 'with gemfile' do
-    let(:data) { "whatever" }
-
-    before do
-      write_file(gemfile_path) { data }
-    end
-
-    describe 'existence' do
-      it { should have_gemfile }
-      it { should_not have_gemfile_erb }
-    end
-
-    describe '#environment' do
-      context 'not defined' do
-        its(:environment) { should be_nil }
-      end
-
-      context 'defined' do
-        let(:environment) { 'test' }
-        let(:data) { <<-GEMFILE }
-# generated by penchant, environment: #{environment}
-GEMFILE
-
-        its(:environment) { should == environment }
-        it { should_not be_deployment }
-      end
-
-      context 'deployment' do
-        let(:environment) { 'test' }
-        let(:data) { <<-GEMFILE }
-# generated by penchant, environment: #{environment}, deployment mode
-GEMFILE
-
-        its(:environment) { should == environment }
-        it { should be_deployment }
-      end
-    end
-
-    describe '#switch_to!' do
-      it 'should raise an exception' do
-        expect { subject.switch_to!(:whatever) }.to raise_error(Errno::ENOENT)
-      end
-    end
-  end
-
-  context 'with gemfile.erb' do
-    let(:erb_data) { 'whatever' }
-
-    before do
-      write_file(gemfile_erb_path) { erb_data }
-    end
-
-    it { should_not have_gemfile }
-    it { should have_gemfile_erb }
-
-    describe '#switch_to!' do
-      let(:erb_data) { <<-ERB }
-<% env :test do %>
-  test
-<% end %>
-
-<% env :not do %>
-  not
-<% end %>
-
-<% no_deployment do %>
-  diddeploy
-<% end %>
-
-all
-ERB
-
-      it 'should render test data' do
-        subject.switch_to!(:test)
-
-        File.read('Gemfile').should include('test')
-        File.read('Gemfile').should include('diddeploy')
-        File.read('Gemfile').should_not include('not')
-        File.read('Gemfile').should include('all')
-      end
-
-      it 'should not render test data' do
-        subject.switch_to!(:not)
-
-        File.read('Gemfile').should_not include('test')
-        File.read('Gemfile').should include('diddeploy')
-        File.read('Gemfile').should include('not')
-        File.read('Gemfile').should include('all')
-      end
-
-      it 'should not render either' do
-        subject.switch_to!
-
-        File.read('Gemfile').should_not include('test')
-        File.read('Gemfile').should_not include('not')
-        File.read('Gemfile').should include('diddeploy')
-        File.read('Gemfile').should include('all')
-      end
-
-      it 'should skip no_deployment sections' do
-        subject.switch_to!(nil, true)
-
-        File.read('Gemfile').should_not include('test')
-        File.read('Gemfile').should_not include('not')
-        File.read('Gemfile').should_not include('diddeploy')
-        File.read('Gemfile').should include('all')
-      end
-
-      it { should_not have_dot_penchant }
-
-      context 'with .penchant' do
-        before do
-          File.open('.penchant', 'wb')
-        end
-
-        it { should have_dot_penchant }
-
-        it 'should process the file' do
-          subject.switch_to!(:not)
-        end
-      end
-    end
-  end
-
-  describe '#switch_to!' do
-    let(:template) { 'source' }
-    let(:gemfile_path) { 'gemfile path' }
-    let(:header) { 'header' }
-
-    let(:gemfile_out) { File.read(gemfile_path) }
-
-    before do
-      gemfile.stubs(:template).returns(template)
-      gemfile.stubs(:gemfile_path).returns(gemfile_path)
-
-      gemfile.expects(:header).returns(header)
-    end
-
-    it 'should write out the new gemfile' do
-      gemfile.switch_to!
-
-      gemfile_out.should include(template)
-      gemfile_out.should include(header)
-    end
-  end
-
-  describe '#header' do
-    subject { gemfile.header }
-
-    let(:env) { 'env' }
-    let(:prior_environment) { 'prior' }
-
-    before do
-      gemfile.stubs(:current_env).returns(env)
-      gemfile.stubs(:environment).returns(prior_environment)
-    end
-
-    context 'not deployment' do
-      before do
-        gemfile.stubs(:is_deployment).returns(false)
-      end
-
-      it { should == "# generated by penchant, environment: #{env}" }
-    end
-
-    context 'deployment' do
-      before do
-        gemfile.stubs(:is_deployment).returns(true)
-      end
-
-      it { should == "# generated by penchant, environment: #{env}, deployment mode (was #{prior_environment})" }
-    end
-  end
-
-  describe '#prior_environment' do
-    subject { gemfile.prior_environment }
-
-    let(:prior) { 'prior' }
-
-    before do
-      gemfile.stubs(:gemfile_header).returns("# header (was #{prior})")
-    end
-
-    it { should == prior }
-  end
-
-  describe '.switch_back!' do
-    let(:gemfile) { stub }
-    let(:fallback_env) { 'env' }
-
-    context 'pre_switch fails' do
-      before do
-        described_class.stubs(:pre_switch).returns(false)
-
-        gemfile.expects(:switch_back!).never
-      end
-
-      it 'should not switch back' do
-        described_class.switch_back!(fallback_env).should be_false
-      end
-    end
-
-    context 'pre_switch succeeds' do
-      before do
-        described_class.stubs(:pre_switch).returns(gemfile)
-
-        gemfile.expects(:switch_back!).with(fallback_env)
-      end
-
-      it 'should switch back' do
-        described_class.switch_back!(fallback_env)
-      end
-    end
-  end
-
-  describe '.pre_switch' do
-    subject { described_class.pre_switch(env, deployment) }
-
-    let(:env) { 'env' }
-    let(:deployment) { 'deployment' }
-
-    context 'no Gemfile.erb' do
-      before do
-        described_class.any_instance.expects(:has_gemfile_erb?).returns(false)
-      end
-
-      it { should be_false }
-    end
-
-    context 'Gemfile.erb' do
-      before do
-        described_class.any_instance.expects(:has_gemfile_erb?).returns(true)
-        described_class.any_instance.expects(:run_dot_penchant!).with(env, deployment)
-      end
-
-      it { should be_a_kind_of(described_class) }
-    end
-  end
-
-  describe '#switch_back!' do
-    let(:fallback_env) { 'fallback' }
-    let(:prior) { 'prior' }
-
-    context 'no prior' do
-      before do
-        gemfile.stubs(:prior_environment).returns(nil)
-
-        gemfile.expects(:switch_to!).with(fallback_env)
-      end
-
-      it 'should proxy through to switch_to!' do
-        gemfile.switch_back!(fallback_env)
-      end
-    end
-
-    context 'prior' do
-      before do
-        gemfile.stubs(:prior_environment).returns(prior)
-
-        gemfile.expects(:switch_to!).with(prior)
-      end
-
-      it 'should proxy through to switch_to!' do
-        gemfile.switch_back!(fallback_env)
-      end
-    end
-  end
-end
-
diff --git a/spec/lib/penchant_spec.rb b/spec/lib/penchant_spec.rb
deleted file mode 100644
index e69de29..0000000
diff --git a/spec/spec_helper.rb b/spec/spec_helper.rb
deleted file mode 100644
index c9de50a..0000000
--- a/spec/spec_helper.rb
+++ /dev/null
@@ -1,6 +0,0 @@
-require 'fakefs/spec_helpers'
-require 'penchant'
-
-RSpec.configure do |c|
-  c.mock_with :mocha
-end