Constants demo
diff --git a/lib/rb/Rakefile b/lib/rb/Rakefile
index b4cb9d6..b33d773 100644
--- a/lib/rb/Rakefile
+++ b/lib/rb/Rakefile
@@ -38,7 +38,7 @@
 end
 
 desc 'Compile the .thrift files for the specs'
-task :'gen-rb' => [:'gen-rb:spec', :'gen-rb:namespaced_spec', :'gen-rb:flat_spec', :'gen-rb:benchmark', :'gen-rb:debug_proto']
+task :'gen-rb' => [:'gen-rb:spec', :'gen-rb:namespaced_spec', :'gen-rb:flat_spec', :'gen-rb:benchmark', :'gen-rb:debug_proto', :'gen-rb:constants_demo']
 namespace :'gen-rb' do
   task :'spec' do
     dir = File.dirname(__FILE__) + '/spec'
@@ -67,6 +67,11 @@
     sh "mkdir", "-p", "test/debug_proto"
     sh THRIFT, '--gen', 'rb', "-o", "test/debug_proto", "../../test/DebugProtoTest.thrift"
   end
+
+  task :'constants_demo' do
+    dir = File.dirname(__FILE__) + '/spec'
+    sh THRIFT, '--gen', 'rb:namespaced', '--recurse', '-o', dir, "../../test/ConstantsDemo.thrift"
+  end
 end
 
 desc "Build the native library"