diff --git a/ood_core.gemspec b/ood_core.gemspec
index 549beb2f..530685b0 100644
--- a/ood_core.gemspec
+++ b/ood_core.gemspec
@@ -31,5 +31,5 @@ Gem::Specification.new do |spec|
   spec.add_development_dependency "pry", "~> 0.10"
   spec.add_development_dependency "timecop", "~> 0.8"
   spec.add_development_dependency "climate_control", "~> 1.2.0"
-  spec.add_development_dependency "minitest", "~> 5"
+  spec.add_development_dependency "minitest", "~> 4"
 end