diff --git a/.gitignore b/.gitignore
index d87d4be..6372741 100644
--- a/.gitignore
+++ b/.gitignore
@@ -15,3 +15,4 @@ spec/reports
 test/tmp
 test/version_tmp
 tmp
+*.gemfile.lock
diff --git a/.travis.yml b/.travis.yml
index 6beb99a..ab82c3a 100644
--- a/.travis.yml
+++ b/.travis.yml
@@ -1,13 +1,25 @@
 language: ruby
+sudo: false
+
+cache:
+  bundler: true
+
 rvm:
   - 2.2
   - 2.3
   - 2.4
   - jruby-19mode # JRuby in 1.9 mode
-# uncomment this line if your project needs to run something other than `rake`:
-script: bundle exec rspec spec
+
+script: bundle exec rake
+
 gemfile:
-  - Gemfile.activesupport51
+  - gemfiles/activesupport_5.1.gemfile
+  - gemfiles/activesupport_5.2.gemfile
+
+matrix:
+  fast_finish: true
+  allow_failures:
+    - rvm: jruby-19mode
 
 before_install:
-  - gem install bundler
\ No newline at end of file
+  - gem update --system
diff --git a/Appraisals b/Appraisals
new file mode 100644
index 0000000..94dbf56
--- /dev/null
+++ b/Appraisals
@@ -0,0 +1,7 @@
+appraise "activesupport-5.1" do
+  gem "activesupport", "~> 5.1.0"
+end
+
+appraise "activesupport-5.2" do
+  gem "activesupport", "~> 5.2.0"
+end
diff --git a/Gemfile.activesupport51 b/Gemfile.activesupport51
deleted file mode 100644
index 65b4cf0..0000000
--- a/Gemfile.activesupport51
+++ /dev/null
@@ -1,4 +0,0 @@
-source "https://rubygems.org"		
-gemspec		
-		
-gem 'activesupport', '~> 5.1'
\ No newline at end of file
diff --git a/Rakefile b/Rakefile
index 16069ae..e621d06 100644
--- a/Rakefile
+++ b/Rakefile
@@ -4,4 +4,7 @@ require "bundler/gem_tasks"
 require 'rspec/core/rake_task'
 
 task :default => :spec
-RSpec::Core::RakeTask.new('spec')
\ No newline at end of file
+if !ENV["APPRAISAL_INITIALIZED"] && !ENV["TRAVIS"]
+  task :default => :appraisal
+end
+RSpec::Core::RakeTask.new('spec')
diff --git a/gemfiles/activesupport_5.1.gemfile b/gemfiles/activesupport_5.1.gemfile
new file mode 100644
index 0000000..a218404
--- /dev/null
+++ b/gemfiles/activesupport_5.1.gemfile
@@ -0,0 +1,7 @@
+# This file was generated by Appraisal
+
+source "https://rubygems.org"
+
+gem "activesupport", "~> 5.1.0"
+
+gemspec path: "../"
diff --git a/gemfiles/activesupport_5.1.gemfile.lock b/gemfiles/activesupport_5.1.gemfile.lock
new file mode 100644
index 0000000..a2cbc8b
--- /dev/null
+++ b/gemfiles/activesupport_5.1.gemfile.lock
@@ -0,0 +1,54 @@
+PATH
+  remote: ..
+  specs:
+    time_difference (0.7.0)
+      activesupport
+
+GEM
+  remote: https://rubygems.org/
+  specs:
+    activesupport (5.1.5)
+      concurrent-ruby (~> 1.0, >= 1.0.2)
+      i18n (~> 0.7)
+      minitest (~> 5.1)
+      tzinfo (~> 1.1)
+    appraisal (2.2.0)
+      bundler
+      rake
+      thor (>= 0.14.0)
+    concurrent-ruby (1.0.5)
+    diff-lcs (1.3)
+    i18n (0.9.5)
+      concurrent-ruby (~> 1.0)
+    minitest (5.11.3)
+    rake (12.3.1)
+    rspec (3.7.0)
+      rspec-core (~> 3.7.0)
+      rspec-expectations (~> 3.7.0)
+      rspec-mocks (~> 3.7.0)
+    rspec-core (3.7.1)
+      rspec-support (~> 3.7.0)
+    rspec-expectations (3.7.0)
+      diff-lcs (>= 1.2.0, < 2.0)
+      rspec-support (~> 3.7.0)
+    rspec-mocks (3.7.0)
+      diff-lcs (>= 1.2.0, < 2.0)
+      rspec-support (~> 3.7.0)
+    rspec-support (3.7.1)
+    thor (0.20.0)
+    thread_safe (0.3.6)
+    tzinfo (1.2.5)
+      thread_safe (~> 0.1)
+
+PLATFORMS
+  ruby
+
+DEPENDENCIES
+  activesupport (~> 5.1.0)
+  appraisal
+  rake
+  rspec (~> 3.7.0)
+  time_difference!
+
+BUNDLED WITH
+   1.16.1
diff --git a/gemfiles/activesupport_5.2.gemfile b/gemfiles/activesupport_5.2.gemfile
new file mode 100644
index 0000000..61c3cca
--- /dev/null
+++ b/gemfiles/activesupport_5.2.gemfile
@@ -0,0 +1,7 @@
+# This file was generated by Appraisal
+
+source "https://rubygems.org"
+
+gem "activesupport", "~> 5.2.0"
+
+gemspec path: "../"
diff --git a/gemfiles/activesupport_5.2.gemfile.lock b/gemfiles/activesupport_5.2.gemfile.lock
new file mode 100644
index 0000000..a1b3a6d
--- /dev/null
+++ b/gemfiles/activesupport_5.2.gemfile.lock
@@ -0,0 +1,54 @@
+PATH
+  remote: ..
+  specs:
+    time_difference (0.7.0)
+      activesupport
+
+GEM
+  remote: https://rubygems.org/
+  specs:
+    activesupport (5.2.0)
+      concurrent-ruby (~> 1.0, >= 1.0.2)
+      i18n (>= 0.7, < 2)
+      minitest (~> 5.1)
+      tzinfo (~> 1.1)
+    appraisal (2.2.0)
+      bundler
+      rake
+      thor (>= 0.14.0)
+    concurrent-ruby (1.0.5)
+    diff-lcs (1.3)
+    i18n (1.0.1)
+      concurrent-ruby (~> 1.0)
+    minitest (5.11.3)
+    rake (12.3.1)
+    rspec (3.7.0)
+      rspec-core (~> 3.7.0)
+      rspec-expectations (~> 3.7.0)
+      rspec-mocks (~> 3.7.0)
+    rspec-core (3.7.1)
+      rspec-support (~> 3.7.0)
+    rspec-expectations (3.7.0)
+      diff-lcs (>= 1.2.0, < 2.0)
+      rspec-support (~> 3.7.0)
+    rspec-mocks (3.7.0)
+      diff-lcs (>= 1.2.0, < 2.0)
+      rspec-support (~> 3.7.0)
+    rspec-support (3.7.1)
+    thor (0.20.0)
+    thread_safe (0.3.6)
+    tzinfo (1.2.5)
+      thread_safe (~> 0.1)
+
+PLATFORMS
+  ruby
+
+DEPENDENCIES
+  activesupport (~> 5.2.0)
+  appraisal
+  rake
+  rspec (~> 3.7.0)
+  time_difference!
+
+BUNDLED WITH
+   1.16.1
diff --git a/time_difference.gemspec b/time_difference.gemspec
index 5ece9c4..8b4a0b2 100644
--- a/time_difference.gemspec
+++ b/time_difference.gemspec
@@ -14,8 +14,9 @@ Gem::Specification.new do |gem|
   gem.version       = "0.7.0"
   gem.license = 'MIT'
 
-  gem.add_runtime_dependency('activesupport', '~> 5.1')
+  gem.add_runtime_dependency('activesupport')
+
+  gem.add_development_dependency('appraisal')
   gem.add_development_dependency('rspec', '~> 3.7.0')
   gem.add_development_dependency('rake')
-
 end