diff --git a/Gemfile b/Gemfile
index 9c1d9e077..42ae10e3c 100644
--- a/Gemfile
+++ b/Gemfile
@@ -21,7 +21,6 @@ group :development do
   gem 'rmail', '~> 1.1'
   gem 'sinatra', '~> 1.4'
   gem 'redis', '~> 3.2'
-  gem 'activesupport', '>= 3.2', '< 5.0'
 end
 
 platforms :jruby do
diff --git a/bin/generate-api b/bin/generate-api
index ff600b452..bebeea5e3 100755
--- a/bin/generate-api
+++ b/bin/generate-api
@@ -1,6 +1,12 @@
 #!/usr/bin/env ruby
 
-require 'thor'
+begin
+  require 'thor'
+rescue LoadError => e
+  puts "Thor is required. Please install the gem with development dependencies."
+  exit 1
+end
+
 require 'open-uri'
 require 'google/apis/discovery_v1'
 require 'logger'
diff --git a/google-api-client.gemspec b/google-api-client.gemspec
index ce6330bb6..e094441d2 100644
--- a/google-api-client.gemspec
+++ b/google-api-client.gemspec
@@ -25,7 +25,9 @@ Gem::Specification.new do |spec|
   spec.add_runtime_dependency 'addressable', '~> 2.3'
   spec.add_runtime_dependency 'mime-types', '>= 1.6'
   spec.add_runtime_dependency 'googleauth', '~> 0.5'
-  spec.add_runtime_dependency 'thor', '~> 0.19'
   spec.add_runtime_dependency 'httpclient', '>= 2.8.1', '< 3.0'
   spec.add_runtime_dependency 'memoist', '~> 0.11'
+  spec.add_development_dependency 'thor', '~> 0.14'
+  spec.add_development_dependency 'activesupport', '>= 3.2', '< 5.0'
+
 end