diff --git a/.gitignore b/.gitignore
index 4288db2..fd69015 100644
--- a/.gitignore
+++ b/.gitignore
@@ -16,3 +16,4 @@ test/tmp
 test/version_tmp
 tmp
 _site
+.vscode
diff --git a/.ruby-version b/.ruby-version
index ec6b00f..73462a5 100644
--- a/.ruby-version
+++ b/.ruby-version
@@ -1 +1 @@
-ruby-2.1.2
+2.5.1
diff --git a/.travis.yml b/.travis.yml
index 4d1ff2e..9323019 100644
--- a/.travis.yml
+++ b/.travis.yml
@@ -1,4 +1,5 @@
 language: ruby
 rvm:
-  - 2.0.0
-  - 2.1.2
+  - 2.5
+  - 2.4
+  - 2.3
diff --git a/Gemfile.lock b/Gemfile.lock
index ded9c99..33ae5c4 100644
--- a/Gemfile.lock
+++ b/Gemfile.lock
@@ -8,37 +8,40 @@ PATH
 GEM
   remote: https://rubygems.org/
   specs:
-    blankslate (2.1.2.4)
-    byebug (3.1.2)
-      columnize (~> 0.8)
-      debugger-linecache (~> 1.2)
-    chunky_png (1.2.7)
-    colorize (0.7.3)
-    columnize (0.8.9)
-    commonjs (0.2.6)
+    byebug (10.0.2)
+    chunky_png (1.3.11)
+    colorize (0.8.1)
+    commonjs (0.2.7)
     compass (0.12.2)
       chunky_png (~> 1.2)
       fssm (>= 0.2.7)
       sass (~> 3.1)
-    debugger-linecache (1.2.0)
+    ffi (1.9.25)
     fssm (0.2.10)
-    less (2.3.1)
-      commonjs (~> 0.2.6)
-    libv8 (3.11.8.17)
-    m (1.3.1)
+    less (2.6.0)
+      commonjs (~> 0.2.7)
+    libv8 (3.16.14.19)
+    m (1.5.1)
       method_source (>= 0.6.7)
       rake (>= 0.9.2.2)
-    method_source (0.8.1)
-    minitest (2.12.1)
-    minitest-rg (1.1.0)
-    parslet (1.6.1)
-      blankslate (~> 2.0)
-    rake (10.0.3)
-    ref (1.0.4)
-    ruby-prof (0.13.0)
-    sass (3.2.7)
-    therubyracer (0.11.4)
-      libv8 (~> 3.11.8.12)
+    method_source (0.9.2)
+    minitest (5.11.3)
+    minitest-rg (5.2.0)
+      minitest (~> 5.0)
+    parslet (1.8.2)
+    rake (12.3.1)
+    rb-fsevent (0.10.3)
+    rb-inotify (0.9.10)
+      ffi (>= 0.5.0, < 2)
+    ref (2.0.0)
+    ruby-prof (0.17.0)
+    sass (3.7.2)
+      sass-listen (~> 4.0.0)
+    sass-listen (4.0.0)
+      rb-fsevent (~> 0.9, >= 0.9.4)
+      rb-inotify (~> 0.9, >= 0.9.7)
+    therubyracer (0.12.3)
+      libv8 (~> 3.16.14.15)
       ref
 
 PLATFORMS
@@ -56,3 +59,6 @@ DEPENDENCIES
   ruby-prof
   sass
   therubyracer
+
+BUNDLED WITH
+   1.16.4
diff --git a/README.md b/README.md
index 5367f7e..ea7df7d 100644
--- a/README.md
+++ b/README.md
@@ -75,7 +75,7 @@ _Please submit [an issue](https://github.com/zmoazeni/csscss/issues/new) if you
 
 I have been asked this a lot, but csscss is intentionally designed this
 way. Check out [this
-post](http://connectionrequired.com/blog/2013/04/why-csscss-doesnt-remove-duplication-for-you/)
+post](https://connectionrequired.com/blog/2013/04/why-csscss-doesnt-remove-duplication-for-you)
 for my reasoning.
 
 ## I found bugs ##
@@ -87,12 +87,6 @@ If you find any issues, please report them on
 Please include the smallest CSS snippet to describe the issue and the
 output you expect to see.
 
-## Who are you? ##
-
-My name is [Zach Moazeni](https://twitter.com/zmoazeni). I work for [an
-awesome company](http://www.getharvest.com/). And [we're
-hiring!](http://www.getharvest.com/careers)
-
 ## I'm a dev, I can help ##
 
 Awesome! Thanks! Here are the steps I ask:
diff --git a/docker-ruby b/docker-ruby
new file mode 100755
index 0000000..33ea97f
--- /dev/null
+++ b/docker-ruby
@@ -0,0 +1,3 @@
+#!/bin/bash
+VERSION=${VERSION:-latest}
+docker run -it --rm -v $(pwd):/app -v csscss_gem_data:/usr/local/bundle -w /app ruby:$VERSION $@
diff --git a/lib/csscss/cli.rb b/lib/csscss/cli.rb
index 0adec9e..2b8430d 100644
--- a/lib/csscss/cli.rb
+++ b/lib/csscss/cli.rb
@@ -64,7 +64,7 @@ def execute
     end
 
     def parse(argv)
-      opts = OptionParser.new do |opts|
+      options = OptionParser.new do |opts|
         opts.banner  = "Usage: csscss [files..]"
         opts.version = Csscss::VERSION
 
@@ -128,11 +128,11 @@ def parse(argv)
           print_help(opts)
         end
       end
-      opts.parse!(argv)
+      options.parse!(argv)
 
-      print_help(opts) if argv.empty?
+      print_help(options) if argv.empty?
     rescue OptionParser::ParseError
-      print_help(opts)
+      print_help(options)
     end
 
     def print_help(opts)
diff --git a/lib/csscss/types.rb b/lib/csscss/types.rb
index 32afd3a..3d01f4d 100644
--- a/lib/csscss/types.rb
+++ b/lib/csscss/types.rb
@@ -1,9 +1,5 @@
 module Csscss
-  class Declaration < Struct.new(:property, :value, :parents)
-    def self.from_csspool(dec)
-      new(dec.property.to_s.downcase, dec.expressions.join(" ").downcase)
-    end
-
+  Declaration = Struct.new(:property, :value, :parents) do
     def self.from_parser(property, value, clean = true)
       value = value.to_s
       property = property.to_s
@@ -79,7 +75,7 @@ def normalize_value(value)
     end
   end
 
-  class Selector < Struct.new(:selectors)
+  Selector = Struct.new(:selectors) do
     def self.from_parser(selectors)
       new(selectors.to_s.strip)
     end
@@ -97,6 +93,5 @@ def inspect
     end
   end
 
-  class Ruleset < Struct.new(:selectors, :declarations)
-  end
+  Ruleset = Struct.new(:selectors, :declarations)
 end
diff --git a/test/csscss/sass_include_extensions_test.rb b/test/csscss/sass_include_extensions_test.rb
index 76ace2e..13f0ea8 100644
--- a/test/csscss/sass_include_extensions_test.rb
+++ b/test/csscss/sass_include_extensions_test.rb
@@ -61,7 +61,7 @@ module Csscss
   /* CSSCSS END MIXIN: foo */ }
       CSS
 
-        Sass::Engine.new("@import '#{f.path}'", syntax: :scss, cache: false).render.must_equal(css)
+        Sass::Engine.new("@import '#{File.basename(f.path)}'", syntax: :scss, cache: false, load_paths: ["/tmp"]).render.must_equal(css)
       end
     end
   end