diff --git a/Gemfile.lock b/Gemfile.lock
index 389d25f..acd1fd6 100644
--- a/Gemfile.lock
+++ b/Gemfile.lock
@@ -2,8 +2,8 @@ PATH
   remote: .
   specs:
     periodicity (0.0.1)
-      activejob
-      activesupport
+      activejob (~> 4.0)
+      activesupport (~> 4.0)
 
 GEM
   remote: https://rubygems.org/
@@ -48,6 +48,6 @@ PLATFORMS
 DEPENDENCIES
   bundler (>= 1.0.0)
   periodicity!
-  rake
+  rake (~> 10.0)
   rspec (~> 3.0)
-  timecop
+  timecop (~> 0.7)
diff --git a/lib/periodicity.rb b/lib/periodicity.rb
index d3aaf08..68b806f 100644
--- a/lib/periodicity.rb
+++ b/lib/periodicity.rb
@@ -4,4 +4,7 @@ end
 require "active_support/all"
 require "periodicity/version.rb"
 require "periodicity/period.rb"
-require "periodicity/rails.rb"
+
+require 'periodicity/extensions/active_job'
+require "periodicity/rails.rb" if defined?(::Rails::Engine)
+require "periodicity/cli.rb"
diff --git a/lib/periodicity/cli.rb b/lib/periodicity/cli.rb
new file mode 100644
index 0000000..8f9569e
--- /dev/null
+++ b/lib/periodicity/cli.rb
@@ -0,0 +1,4 @@
+module Periodicity
+  class Cli
+  end
+end
diff --git a/lib/periodicity/rails.rb b/lib/periodicity/rails.rb
index f4f79ce..020b8e2 100644
--- a/lib/periodicity/rails.rb
+++ b/lib/periodicity/rails.rb
@@ -1,7 +1,7 @@
 module Periodicity
   def self.hook_rails!
     ActiveSupport.on_load(:active_job) do
-      extend Sidekiq::Extensions::ActiveJob
+      extend Periodicity::Extensions::ActiveJob
     end
   end
 
@@ -9,5 +9,5 @@ module Periodicity
     initializer 'periodicity' do
       Periodicity.hook_rails!
     end
-  end if defined?(::Rails)
+  end
 end
diff --git a/periodicity.gemspec b/periodicity.gemspec
index 568d11d..be0cbf6 100644
--- a/periodicity.gemspec
+++ b/periodicity.gemspec
@@ -8,16 +8,17 @@ Gem::Specification.new do |s|
   s.email       = ["plashchynski@gmail.com"]
   s.homepage    = "https://github.com/plashchynski/periodicity"
   s.description = s.summary = "Job scheduler for Rails"
+  s.license     = "Apache-2.0"
 
   s.required_rubygems_version = ">= 1.3.6"
   s.rubyforge_project         = "periodicity"
 
-  s.add_runtime_dependency      "activejob"
-  s.add_runtime_dependency      "activesupport"
-  s.add_development_dependency  "rake"
+  s.add_runtime_dependency      "activejob", "~> 4.0"
+  s.add_runtime_dependency      "activesupport", "~> 4.0"
+  s.add_development_dependency  "rake", "~> 10.0"
   s.add_development_dependency  "bundler", ">= 1.0.0"
   s.add_development_dependency  "rspec", "~> 3.0"
-  s.add_development_dependency  "timecop"
+  s.add_development_dependency  "timecop", "~> 0.7"
 
   s.files        = `git ls-files`.split("\n")
   s.executables  = `git ls-files`.split("\n").map{|f| f =~ /^bin\/(.*)/ ? $1 : nil}.compact