diff --git a/.travis.yml b/.travis.yml
index 4a33b58..44c9d45 100644
--- a/.travis.yml
+++ b/.travis.yml
@@ -3,6 +3,8 @@ language: ruby
 cache: bundler
 env:
   - CI=true
+before_install:
+  - gem install bundler
 rvm:
   - 2.0.0
   - 2.1.6
diff --git a/gemfiles/Gemfile.base b/gemfiles/Gemfile.base
index 421e0cd..e6089c4 100644
--- a/gemfiles/Gemfile.base
+++ b/gemfiles/Gemfile.base
@@ -2,6 +2,8 @@ source "http://rubygems.org"
 
 gemspec path: File.expand_path('../..', __FILE__)
 
+ruby RUBY_VERSION
+
 gem 'rake'
 gem 'rspec'
 gem 'timecop'
@@ -15,12 +17,13 @@ gem 'simplecov'
 
 gem 'redis'
 gem 'fakeredis'
-gem 'sqlite3'
+gem 'sqlite3', platform: :mri
 gem 'sequel'
 
 gem 'delayed_job', require: false
 gem 'resque', require: false
 
-unless RUBY_VERSION.to_i <= 1
-  gem 'sidekiq', require: false
+# Freeze Sidekiq to < 5 in Ruby 2.2 Gemfiles
+if RUBY_VERSION >= '2'
+  gem 'sidekiq', (RUBY_VERSION >= '2.2.2' ? '~> 5' : '~> 4'), require: false
 end
diff --git a/gemfiles/Gemfile.rails-5.0.x b/gemfiles/Gemfile.rails-5.0.x
index 692d6c1..0353904 100644
--- a/gemfiles/Gemfile.rails-5.0.x
+++ b/gemfiles/Gemfile.rails-5.0.x
@@ -1,4 +1,4 @@
 eval_gemfile File.expand_path('../Gemfile.base', __FILE__)
 
 gem 'rails', '~> 5.0.0'
-gem 'sinatra', git: 'https://github.com/sinatra/sinatra.git'
+gem 'sinatra'