diff --git a/lib/searchkick.rb b/lib/searchkick.rb
index d0c1897..ef34956 100644
--- a/lib/searchkick.rb
+++ b/lib/searchkick.rb
@@ -1,3 +1,4 @@
+require "active_model"
 require "elasticsearch/model"
 require "searchkick/version"
 require "searchkick/index"
@@ -32,8 +33,5 @@ module Searchkick
   end
 end
 
-require "active_record" # TODO remove
-
 # TODO find better ActiveModel hook
-ActiveModel::Callbacks.send(:include, Searchkick::Model) if defined?(ActiveModel)
-ActiveRecord::Base.send(:extend, Searchkick::Model) if defined?(ActiveRecord)
+ActiveModel::Callbacks.send(:include, Searchkick::Model)
diff --git a/searchkick.gemspec b/searchkick.gemspec
index f9660ce..bedfcfc 100644
--- a/searchkick.gemspec
+++ b/searchkick.gemspec
@@ -18,6 +18,7 @@ Gem::Specification.new do |spec|
   spec.test_files    = spec.files.grep(%r{^(test|spec|features)/})
   spec.require_paths = ["lib"]
 
+  spec.add_dependency "activemodel"
   spec.add_dependency "elasticsearch-model"
 
   spec.add_development_dependency "bundler", "~> 1.3"
--
libgit2 0.21.0