diff --git a/deploy-agent.gemspec b/deploy-agent.gemspec
index 7d8be37..037238b 100644
--- a/deploy-agent.gemspec
+++ b/deploy-agent.gemspec
@@ -15,7 +15,7 @@ Gem::Specification.new do |s|
   s.bindir      = 'bin'
   s.executables << 'deploy-agent'
 
-  s.add_dependency 'nio4r', '2.1.0'
-  s.add_dependency 'rb-readline', '0.5.5'
-  s.add_dependency 'timers', '4.1.2'
+  s.add_dependency 'nio4r', '~> 2.7'
+  s.add_dependency 'rb-readline', '~> 0.5'
+  s.add_dependency 'timers', '~> 4.3'
 end
diff --git a/lib/deploy_agent/agent.rb b/lib/deploy_agent/agent.rb
index 2ef672f..8db8aaa 100644
--- a/lib/deploy_agent/agent.rb
+++ b/lib/deploy_agent/agent.rb
@@ -1,5 +1,3 @@
-gem 'nio4r', '2.1.0'
-gem 'timers', '4.1.2'
 require 'nio'
 require 'timers'
 require 'logger'