diff --git a/.travis.yml b/.travis.yml
index 8bcfc97..1cf4b3b 100644
--- a/.travis.yml
+++ b/.travis.yml
@@ -5,6 +5,7 @@ rvm:
   - 2.2
   - rbx-2
   - ruby-head
+  - jruby-head
 
 env:
   - RAILS_ENV=test COVERAGE=true
@@ -22,3 +23,4 @@ matrix:
   allow_failures:
     - rvm: rbx-2
     - rvm: ruby-head
+    - rvm: jruby-head
diff --git a/Gemfile b/Gemfile
index 9ca9943..e9ca6b5 100644
--- a/Gemfile
+++ b/Gemfile
@@ -55,7 +55,8 @@ gem 'flowdock'
 gem 'omniauth-github'
 
 gem 'ri_cal'
-gem 'yajl-ruby', :require => "yajl"
+gem 'yajl-ruby', platform: 'ruby'
+gem 'json', platform: 'jruby'
 
 group :development, :test do
   gem 'airbrake', :require => false
@@ -72,7 +73,7 @@ group :development do
 
   # better errors
   gem 'better_errors'
-  gem 'binding_of_caller'
+  gem 'binding_of_caller', platform: 'ruby'
   gem 'meta_request'
   gem 'foreman', :require => false
 end
@@ -96,7 +97,7 @@ end
 
 group :heroku, :production do
   gem 'rails_12factor', require: !!ENV["HEROKU"]
-  gem 'unicorn', :require => false
+  gem 'unicorn', require: false, platform: 'ruby'
 end
 
 gem 'sass-rails'
diff --git a/Gemfile.lock b/Gemfile.lock
index 2f13207..63a0011 100644
--- a/Gemfile.lock
+++ b/Gemfile.lock
@@ -51,12 +51,14 @@ GEM
       json
     arel (5.0.1.20140414130214)
     bcrypt (3.1.9)
+    bcrypt (3.1.9-java)
     better_errors (1.0.1)
       coderay (>= 1.0.0)
       erubis (>= 2.6.6)
     binding_of_caller (0.7.2)
       debug_inspector (>= 0.0.1)
     bson (2.3.0)
+    bson (2.3.0-java)
     builder (3.2.2)
     byebug (2.7.0)
       columnize (~> 0.3)
@@ -132,6 +134,7 @@ GEM
     fabrication (2.9.0)
     faraday (0.8.9)
       multipart-post (~> 1.2.0)
+    ffi (1.9.6-java)
     flowdock (0.3.1)
       httparty (~> 0.7)
       multi_json
@@ -160,6 +163,7 @@ GEM
       railties (>= 3.0, < 5.0)
       thor (>= 0.14, < 2.0)
     json (1.8.2)
+    json (1.8.2-java)
     jwt (0.1.8)
       multi_json (>= 1.5)
     kaminari (0.14.1)
@@ -168,6 +172,9 @@ GEM
     kgio (2.9.2)
     launchy (2.4.3)
       addressable (~> 2.3)
+    launchy (2.4.3-java)
+      addressable (~> 2.3)
+      spoon (~> 0.0.1)
     mail (2.6.3)
       mime-types (>= 1.16, < 3)
     meta_request (0.2.8)
@@ -204,6 +211,7 @@ GEM
     net-ssh (2.9.1)
     nokogiri (1.6.5)
       mini_portile (~> 0.6.0)
+    nokogiri (1.6.5-java)
     oauth2 (0.8.1)
       faraday (~> 0.8)
       httpauth (~> 0.1)
@@ -239,6 +247,11 @@ GEM
       coderay (~> 1.0.5)
       method_source (~> 0.8)
       slop (~> 3.4)
+    pry (0.9.12.2-java)
+      coderay (~> 1.0.5)
+      method_source (~> 0.8)
+      slop (~> 3.4)
+      spoon (~> 0.0)
     pry-byebug (1.3.2)
       byebug (~> 2.7)
       pry (~> 0.9.12)
@@ -332,6 +345,8 @@ GEM
       simplecov-html (~> 0.7.1)
     simplecov-html (0.7.1)
     slop (3.4.6)
+    spoon (0.0.4)
+      ffi
     sprockets (2.12.3)
       hike (~> 1.2)
       multi_json (~> 1.0)
@@ -351,6 +366,7 @@ GEM
       power_assert
     thor (0.19.1)
     thread_safe (0.3.4)
+    thread_safe (0.3.4-java)
     tilt (1.4.1)
     timecop (0.6.3)
     tins (0.12.0)
@@ -369,6 +385,8 @@ GEM
       rack (>= 1.0)
     websocket-driver (0.5.1)
       websocket-extensions (>= 0.1.0)
+    websocket-driver (0.5.1-java)
+      websocket-extensions (>= 0.1.0)
     websocket-extensions (0.1.1)
     xmpp4r (0.5.5)
     xpath (2.0.0)
@@ -376,6 +394,7 @@ GEM
     yajl-ruby (1.1.0)
 
 PLATFORMS
+  java
   ruby
 
 DEPENDENCIES
@@ -411,6 +430,7 @@ DEPENDENCIES
   htmlentities
   httparty
   jquery-rails (~> 2.1.4)
+  json
   kaminari (>= 0.14.1)
   launchy
   meta_request
diff --git a/app/controllers/api/v1/notices_controller.rb b/app/controllers/api/v1/notices_controller.rb
index 3b36b6d..f16710f 100644
--- a/app/controllers/api/v1/notices_controller.rb
+++ b/app/controllers/api/v1/notices_controller.rb
@@ -16,7 +16,7 @@ class Api::V1::NoticesController < ApplicationController
     end
 
     respond_to do |format|
-      format.any(:html, :json) { render :json => Yajl.dump(results) } # render JSON if no extension specified on path
+      format.any(:html, :json) { render :json => JSON.dump(results) } # render JSON if no extension specified on path
       format.xml  { render :xml  => results }
     end
   end
diff --git a/app/controllers/api/v1/problems_controller.rb b/app/controllers/api/v1/problems_controller.rb
index 8225a03..76f6282 100644
--- a/app/controllers/api/v1/problems_controller.rb
+++ b/app/controllers/api/v1/problems_controller.rb
@@ -32,7 +32,7 @@ class Api::V1::ProblemsController < ApplicationController
     end
 
     respond_to do |format|
-      format.any(:html, :json) { render :json => Yajl.dump(results) } # render JSON if no extension specified on path
+      format.any(:html, :json) { render :json => JSON.dump(results) } # render JSON if no extension specified on path
       format.xml  { render :xml  => results }
     end
   end
diff --git a/app/controllers/api/v1/stats_controller.rb b/app/controllers/api/v1/stats_controller.rb
index fcd646f..67f7a92 100644
--- a/app/controllers/api/v1/stats_controller.rb
+++ b/app/controllers/api/v1/stats_controller.rb
@@ -18,7 +18,7 @@ class Api::V1::StatsController < ApplicationController
     }
 
     respond_to do |format|
-      format.any(:html, :json) { render :json => Yajl.dump(stats) } # render JSON if no extension specified on path
+      format.any(:html, :json) { render :json => JSON.dump(stats) } # render JSON if no extension specified on path
       format.xml  { render :xml  => stats }
     end
   end
diff --git a/config/boot.rb b/config/boot.rb
index 5e5f0c1..36b1587 100644
--- a/config/boot.rb
+++ b/config/boot.rb
@@ -2,3 +2,11 @@
 ENV['BUNDLE_GEMFILE'] ||= File.expand_path('../../Gemfile', __FILE__)
 
 require 'bundler/setup' if File.exist?(ENV['BUNDLE_GEMFILE'])
+require 'json'
+
+begin
+  # try to use Yajl, the json_gem compatibility layer must be loaded after json
+  require 'yajl/json_gem'
+rescue LoadError
+  # fail silently because json gem is fine
+end
--
libgit2 0.21.2