try using rack/cache with memcached

Gemfile

@@ -8,8 +8,10 @@ gem 'travis-core',    github: 'travis-ci/travis-core', branch: 'sf-travis-api'
 gem 'hubble',         github: 'roidrage/hubble'
 gem 'yard-sinatra',   github: 'rkh/yard-sinatra'
 gem 'rack-contrib',   github: 'rack/rack-contrib'
+gem 'rack-cache',     '~> 1.2'
 gem 'gh',             github: 'rkh/gh'
 gem 'bunny'
+gem 'dalli'
 
 group :test do
   gem 'rspec',        '~> 2.11'

Gemfile.lock

@@ -118,6 +118,7 @@ GEM
     builder (3.0.3)
     bunny (0.8.0)
     daemons (1.1.9)
+    dalli (2.2.1)
     data_migrations (0.0.1)
       activerecord
       rake
@@ -235,6 +236,7 @@ PLATFORMS
 
 DEPENDENCIES
   bunny
+  dalli
   database_cleaner (~> 0.8.0)
   factory_girl (~> 2.4.0)
   foreman
@@ -242,6 +244,7 @@ DEPENDENCIES
   hubble!
   micro_migrations!
   mocha (~> 0.12)
+  rack-cache (~> 1.2)
   rack-contrib!
   rake (~> 0.9.2)
   rerun

lib/travis/api/app.rb

@@ -3,6 +3,7 @@ require 'backports'
 require 'rack'
 require 'rack/protection'
 require 'rack/contrib'
+require 'rack/cache'
 require 'active_record'
 require 'redis'
 require 'gh'
@@ -55,6 +56,14 @@ module Travis::Api
         use Hubble::Rescuer, env: Travis.env, codename: ENV['CODENAME'] if Endpoint.production? && ENV['HUBBLE_ENDPOINT']
         use Rack::Protection::PathTraversal
         use Rack::SSL if Endpoint.production?
+
+        if memcache_servers = ENV['MEMCACHE_SERVERS']
+          use Rack::Cache,
+            verbose: true,
+            metastore:   "memcached://#{memcache_servers}",
+            entitystore: "memcached://#{memcache_servers}"
+        end
+
         use Rack::Deflater
         use Rack::PostBodyContentTypeParser
         use Rack::JSONP