diff --git a/mini_portile2.gemspec b/mini_portile2.gemspec
index e57ec4d..8fbf41e 100644
--- a/mini_portile2.gemspec
+++ b/mini_portile2.gemspec
@@ -31,11 +31,11 @@ Gem::Specification.new do |spec|
   spec.test_files    = spec.files.grep(%r{^(test|spec|features|examples)/})
   spec.require_paths = ["lib"]
 
-  spec.add_development_dependency "bundler", "~> 1.7"
+  spec.add_development_dependency "bundler", "~> 1.17"
   spec.add_development_dependency "rake", "~> 12.0"
-  spec.add_development_dependency "minitest", "~> 5.8"
-  spec.add_development_dependency "minitest-hooks", "~> 1.4"
-  spec.add_development_dependency "minitar", "~> 0.5"
+  spec.add_development_dependency "minitest", "~> 5.11"
+  spec.add_development_dependency "minitest-hooks", "~> 1.5.0"
+  spec.add_development_dependency "minitar", "~> 0.7"
   spec.add_development_dependency "concourse", "~> 0.16"
 
   spec.required_ruby_version = ">= 1.9.2"