diff --git a/.gitignore b/.gitignore
index c6de9ad..af948e3 100644
--- a/.gitignore
+++ b/.gitignore
@@ -1,9 +1,11 @@
 *.gem
-*.rbc
+*~
 .bundle
+.rvmrc
 .yardoc
 Gemfile.lock
 coverage/*
 doc/*
 log/*
+measurement/*
 pkg/*
diff --git a/CONTRIBUTING.md b/CONTRIBUTING.md
index b54b30e..c9e45f9 100644
--- a/CONTRIBUTING.md
+++ b/CONTRIBUTING.md
@@ -39,8 +39,8 @@ Ideally, a bug report should include a pull request with failing specs.
 7. Run `open coverage/index.html`. If your changes are not completely covered
    by your tests, return to step 3.
 8. Add documentation for your feature or bug fix.
-9. Run `bundle exec rake yard`. If your changes are not 100% documented, go
-   back to step 8.
+9. Run `bundle exec rake verify_measurements`. If your changes are not 100%
+   documented, go back to step 8.
 10. Add, commit, and push your changes.
 11. [Submit a pull request.][pr]
 
diff --git a/Gemfile b/Gemfile
index 767ed09..43b12ee 100644
--- a/Gemfile
+++ b/Gemfile
@@ -15,12 +15,14 @@ group :development do
 end
 
 group :test do
+  gem 'backports'
   gem 'coveralls', :require => false
   gem 'mime-types', '~> 1.25', :platforms => [:jruby, :ruby_18]
   gem 'rspec', '>= 2.11'
   gem 'rubocop', '>= 0.16', :platforms => [:ruby_19, :ruby_20, :ruby_21]
   gem 'simplecov', :require => false
   gem 'webmock'
+  gem 'yardstick'
 end
 
 platforms :rbx do
diff --git a/Rakefile b/Rakefile
index e001d6c..930005f 100644
--- a/Rakefile
+++ b/Rakefile
@@ -29,4 +29,14 @@ end
 require 'yard'
 YARD::Rake::YardocTask.new
 
-task :default => [:spec, :rubocop]
+require 'yardstick/rake/measurement'
+Yardstick::Rake::Measurement.new do |measurement|
+  measurement.output = 'measurement/report.txt'
+end
+
+require 'yardstick/rake/verify'
+Yardstick::Rake::Verify.new do |verify|
+  verify.threshold = 55.7
+end
+
+task :default => [:spec, :rubocop, :verify_measurements]