diff --git a/actionagent/actionagent.gemspec b/actionagent/actionagent.gemspec
index d7db4215..6e1cc1e1 100644
--- a/actionagent/actionagent.gemspec
+++ b/actionagent/actionagent.gemspec
@@ -57,6 +57,6 @@ Gem::Specification.new do |spec|
   # `activeagent` could never declare, since solid_agent depends on it.
   spec.add_dependency "solid_agent", ">= 0.1"
 
-  spec.add_development_dependency "minitest", "~> 5.0"
+  spec.add_development_dependency "minitest", "~> 6.0"
   spec.add_development_dependency "sqlite3"
 end
diff --git a/activeagent.gemspec b/activeagent.gemspec
index 3b1aec52..45ede8f2 100644
--- a/activeagent.gemspec
+++ b/activeagent.gemspec
@@ -44,7 +44,7 @@ Gem::Specification.new do |spec|
   spec.add_development_dependency "ostruct"
   spec.add_development_dependency "puma"
   spec.add_development_dependency "sqlite3"
-  spec.add_development_dependency "minitest", "~> 5.0"
+  spec.add_development_dependency "minitest", "~> 6.0"
   # Older vcr 6.3.x breaks on Ruby 3.5+/4.0 with a CGI.parse NameError. Keep a
   # floor so no gemfile resolves back to the broken version.
   spec.add_development_dependency "vcr", ">= 6.4"