diff --git a/CHANGELOG.md b/CHANGELOG.md
index bf1f58c..cd411e3 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -1,3 +1,12 @@
+# 0.4.6
+
+* [fix] Implement new engine interface for future sprockets versions #70
+* [bugfix] Fix issue where helper is not a defined method on controller (e.g. ActionController::API:Class) #65
+
+# 0.4.5
+
+* [bugfix] fix sprockets engine registering for older sprocket-rails versions #68
+
 # 0.4.4
 
 * [bugfix] fix compatibility with with sprockts-rails version 3.x, see #62
diff --git a/README.md b/README.md
index 77af792..d1b3805 100644
--- a/README.md
+++ b/README.md
@@ -4,9 +4,8 @@ Gem for splitting up stylesheets that go beyond the IE limit of 4096 selectors,
 
 ### Development status
 
-Since the original developers of this gem are not actively using it in any project at the moment, it is currently in **limited maintenance** mode.  Issues are read and pull requests will be reviewed and merged, but there is currently no acitve maintenance/development.
-
-If you are an active user of the gem and would be able to help out maintaining it, it would be greatly appreciated.  Just look at the current issues/pull requests.
+Fortunately, the problem of too large CSS files is long gone. This repo is unmaintained.
+It remains as an artefact of dark times in the history of web browsers.
 
 ## Installation
 
@@ -100,14 +99,13 @@ Since 0.4.1 in development split stylesheets have `debug: false` option by defau
 
 ## Credits & License
 
-This is a joint project by the two German Rails shops [Zweitag](http://zweitag.de) and [Railslove](http://railslove.com), therefore the GitHub name "Zweilove".
+This is a joint project by the two German Rails shops [Zweitag](https://zweitag.de) and [Railslove](https://railslove.com), therefore the GitHub name "Zweilove".
 
-The original code was written by [Christian Peters](mailto:christian.peters@zweitag.de) and [Thomas Hollstegge](mailto:thomas.hollstegge@zweitag.de) (see this [Gist](https://gist.github.com/2398394)) and turned into a gem by [Jakob Hilden](mailto:jakobhilden@gmail.com).
+The original code was written by Christian Peters and Thomas Hollstegge (see this [Gist](https://gist.github.com/2398394)) and turned into a gem by Jakob Hilden.
 
 **Major Contributors**
 
 * [@Umofomia](https://github.com/Umofomia)
 * [@kruszczynski](https://github.com/kruszczynski)
 
-This project rocks and uses MIT-LICENSE.
-
+This project uses MIT-LICENSE.
diff --git a/lib/css_splitter/engine.rb b/lib/css_splitter/engine.rb
index 2f50392..05a1fae 100644
--- a/lib/css_splitter/engine.rb
+++ b/lib/css_splitter/engine.rb
@@ -1,14 +1,19 @@
 module CssSplitter
   class Engine < ::Rails::Engine
     initializer 'css_splitter.sprockets_engine', after: 'sprockets.environment', group: :all do |app|
-      app.config.assets.configure do |assets|
-        assets.register_bundle_processor 'text/css', CssSplitter::SprocketsEngine
+      if app.config.assets.public_methods.include? :configure
+        app.config.assets.configure do |assets|
+          assets.register_bundle_processor 'text/css', CssSplitter::SprocketsEngine
+        end
+      else
+        app.assets.register_bundle_processor 'text/css', CssSplitter::SprocketsEngine
       end
     end
 
     initializer 'css_splitter.action_controller' do |app|
       ActiveSupport.on_load :action_controller do
-        helper CssSplitter::ApplicationHelper
+        # Not all controllers use helpers (such as API based controllers)
+        helper CssSplitter::ApplicationHelper if respond_to?(:helper)
       end
     end
   end
diff --git a/lib/css_splitter/sprockets_engine.rb b/lib/css_splitter/sprockets_engine.rb
index f6ae2a8..551af8c 100644
--- a/lib/css_splitter/sprockets_engine.rb
+++ b/lib/css_splitter/sprockets_engine.rb
@@ -10,6 +10,22 @@ def self.engine_initialized?
     def prepare
     end
 
+    def self.call(input)
+      data_in = input[:data]
+
+      # Instantiate Sprockets::Context to pass along helper methods for Tilt
+      # processors
+      context = input[:environment].context_class.new(input)
+
+      # Pass the asset file contents as a block to the template engine,
+      # then get the results of the engine rendering
+      engine = self.new { data_in }
+      rendered_data = engine.render(context, {})
+
+      # Return the data and any metadata (ie file dependencies, etc)
+      context.metadata.merge(data: rendered_data.to_str)
+    end
+
     def evaluate(scope, locals, &block)
       # Evaluate the split if the asset is named with a trailing _split2, _split3, etc.
       if scope.logical_path =~ /_split(\d+)$/
diff --git a/lib/css_splitter/version.rb b/lib/css_splitter/version.rb
index 06e4f4e..57859d1 100644
--- a/lib/css_splitter/version.rb
+++ b/lib/css_splitter/version.rb
@@ -1,3 +1,3 @@
 module CssSplitter
-  VERSION = "0.4.4"
+  VERSION = "0.4.6"
 end
diff --git a/test/css_splitter_test.rb b/test/css_splitter_test.rb
index 5090a3d..012cf89 100644
--- a/test/css_splitter_test.rb
+++ b/test/css_splitter_test.rb
@@ -13,18 +13,17 @@ class CssSplitterTest < ActiveSupport::TestCase
     part2 = "#test{background-color:green}" * CssSplitter::Splitter::MAX_SELECTORS_DEFAULT
     part3 = "#test{background-color:blue}"
 
-    assert_equal "#{part1}#{part2}#{part3}\n",  assets["erb_stylesheet"].to_s
-    assert_equal "#{part2}\n",                  assets["erb_stylesheet_split2"].to_s
-    assert_equal "#{part3}\n",                  assets["erb_stylesheet_split3"].to_s
+    assert_equal "#{part1}#{part2}#{part3}",  assets["erb_stylesheet"].to_s.gsub(/\s/, '')
+    assert_equal "#{part2}",                  assets["erb_stylesheet_split2"].to_s.gsub(/\s/, '')
+    assert_equal "#{part3}",                  assets["erb_stylesheet_split3"].to_s.gsub(/\s/, '')
   end
 
   test "asset pipeline stylesheet splitting on stylesheet combined using requires" do
     red   = "#test{background-color:red}"   * 100
     green = "#test{background-color:green}" * CssSplitter::Splitter::MAX_SELECTORS_DEFAULT
     blue  = "#test{background-color:blue}"
-
-    assert_equal "#{red}#{green}#{blue}\n",                           assets["combined"].to_s
-    assert_equal "#{"#test{background-color:green}" * 100}#{blue}\n", assets["combined_split2"].to_s
+    assert_equal "#{red}#{green}#{blue}",                           assets["combined"].to_s.gsub(/\s/, '')
+    assert_equal "#{"#test{background-color:green}" * 100}#{blue}", assets["combined_split2"].to_s.gsub(/\s/, '')
   end
 
   private
diff --git a/test/dummy/config/application.rb b/test/dummy/config/application.rb
index 4e42755..7a5b60e 100644
--- a/test/dummy/config/application.rb
+++ b/test/dummy/config/application.rb
@@ -38,7 +38,8 @@ class Application < Rails::Application
 
     # Configure sensitive parameters which will be filtered from the log file.
     config.filter_parameters += [:password]
-
+    config.sass.line_comments = false
+    config.assets.compress = true
     # Enable escaping HTML in JSON.
     config.active_support.escape_html_entities_in_json = true