diff --git a/samples/Gemfile b/samples/Gemfile
index b1748272..0679d9f8 100644
--- a/samples/Gemfile
+++ b/samples/Gemfile
@@ -19,5 +19,5 @@ gem "google-cloud-storage"
 group :test do
   gem "minitest", "~> 5.16"
   gem "minitest-focus", "~> 1.1"
-  gem "toys-core", "~> 0.14.4"
+  gem "toys-core", ">= 0.14.4", "< 0.16"
 end