diff --git a/Rakefile b/Rakefile
index 08186e27..9ac6189d 100644
--- a/Rakefile
+++ b/Rakefile
@@ -1,7 +1,7 @@
-require 'json'
 require 'rake/clean'
 require 'rake/testtask'
 require 'yaml'
+require 'yajl'
 
 task :default => :test
 
@@ -19,15 +19,13 @@ end
 
 task :samples do
   require 'linguist/samples'
-  require 'yajl'
-  data = Linguist::Samples.data
-  json = Yajl::Encoder.encode(data, :pretty => true)
-  File.open('lib/linguist/samples.json', 'w') { |io| io.write json }
+  json = Yajl.dump(Linguist::Samples.data, :pretty => true)
+  File.write 'lib/linguist/samples.json', json
 end
 
 task :build_gem => :samples do
   languages = YAML.load_file("lib/linguist/languages.yml")
-  File.write("lib/linguist/languages.json", JSON.dump(languages))
+  File.write("lib/linguist/languages.json", Yajl.dump(languages))
   `gem build github-linguist.gemspec`
   File.delete("lib/linguist/languages.json")
 end
@@ -71,11 +69,11 @@ namespace :benchmark do
     reference_file = ENV["REFERENCE"]
     candidate_file = ENV["CANDIDATE"]
 
-    reference = JSON.parse(File.read(reference_file))
+    reference = Yajl.load(File.read(reference_file))
     reference_counts = Hash.new(0)
     reference.each { |filename, language| reference_counts[language] += 1 }
 
-    candidate = JSON.parse(File.read(candidate_file))
+    candidate = Yajl.load(File.read(candidate_file))
     candidate_counts = Hash.new(0)
     candidate.each { |filename, language| candidate_counts[language] += 1 }
 
@@ -125,14 +123,12 @@ namespace :classifier do
 
   def each_public_gist
     require 'open-uri'
-    require 'json'
-
     url = "https://api.github.com/gists/public"
 
     loop do
       resp = open(url)
       url = resp.meta['link'][/<([^>]+)>; rel="next"/, 1]
-      gists = JSON.parse(resp.read)
+      gists = Yajl.load(resp.read)
 
       for gist in gists
         for filename, attrs in gist['files']
diff --git a/github-linguist.gemspec b/github-linguist.gemspec
index ff086b04..6f3317f3 100644
--- a/github-linguist.gemspec
+++ b/github-linguist.gemspec
@@ -18,7 +18,6 @@ Gem::Specification.new do |s|
   s.add_dependency 'mime-types',      '~> 1.19'
   s.add_dependency 'pygments.rb',     '~> 0.6.0'
 
-  s.add_development_dependency 'json'
   s.add_development_dependency 'mocha'
   s.add_development_dependency 'pry'
   s.add_development_dependency 'rake'
diff --git a/lib/linguist/language.rb b/lib/linguist/language.rb
index 666c75df..49c4a6be 100644
--- a/lib/linguist/language.rb
+++ b/lib/linguist/language.rb
@@ -2,7 +2,7 @@ require 'escape_utils'
 require 'pygments'
 require 'yaml'
 begin
-  require 'json'
+  require 'yajl'
 rescue LoadError
 end
 
@@ -533,8 +533,8 @@ module Linguist
   languages_yml = File.expand_path("../languages.yml", __FILE__)
   languages_json = File.expand_path("../languages.json", __FILE__)
 
-  if File.exist?(languages_json) && defined?(JSON)
-    languages = JSON.load(File.read(languages_json))
+  if File.exist?(languages_json) && defined?(Yajl)
+    languages = Yajl.load(File.read(languages_json))
   else
     languages = YAML.load_file(languages_yml)
   end
diff --git a/lib/linguist/samples.rb b/lib/linguist/samples.rb
index 920bb87e..82c011b1 100644
--- a/lib/linguist/samples.rb
+++ b/lib/linguist/samples.rb
@@ -1,5 +1,5 @@
 begin
-  require 'json'
+  require 'yajl'
 rescue LoadError
   require 'yaml'
 end
@@ -19,7 +19,7 @@ module Linguist
     # Hash of serialized samples object
     def self.cache
       @cache ||= begin
-        serializer = defined?(JSON) ? JSON : YAML
+        serializer = defined?(Yajl) ? Yajl : YAML
         serializer.load(File.read(PATH))
       end
     end
diff --git a/test/test_samples.rb b/test/test_samples.rb
index 899992dd..992618cf 100644
--- a/test/test_samples.rb
+++ b/test/test_samples.rb
@@ -16,11 +16,11 @@ class TestSamples < Test::Unit::TestCase
       warn "Samples database is out of date. Run `bundle exec rake samples`."
 
       expected = Tempfile.new('expected.json')
-      expected.write Yajl::Encoder.encode(serialized, :pretty => true)
+      expected.write Yajl.dump(serialized, :pretty => true)
       expected.close
 
       actual = Tempfile.new('actual.json')
-      actual.write Yajl::Encoder.encode(latest, :pretty => true)
+      actual.write Yajl.dump(latest, :pretty => true)
       actual.close
 
       expected.unlink