diff --git a/Gemfile b/Gemfile
index 51acf3f7d2..393db50682 100644
--- a/Gemfile
+++ b/Gemfile
@@ -1,5 +1,6 @@
 source :rubygems
 
 gem "rake"
+gem "json", :platform => :jruby
 
 gemspec
diff --git a/Gemfile.lock b/Gemfile.lock
index ffa5599bfa..eec7aa9a65 100644
--- a/Gemfile.lock
+++ b/Gemfile.lock
@@ -25,6 +25,7 @@ PLATFORMS
   ruby
 
 DEPENDENCIES
+  json
   kramdown (~> 0.13.7)
   money!
   rake