diff --git a/.fixtures.yml b/.fixtures.yml
index b25e8c459..f1df77eca 100644
--- a/.fixtures.yml
+++ b/.fixtures.yml
@@ -1,7 +1,9 @@
 fixtures:
   repositories:
     facts: 'https://github.com/puppetlabs/puppetlabs-facts.git'
-    puppet_agent: 'https://github.com/puppetlabs/puppetlabs-puppet_agent.git'
+    puppet_agent:
+      repo: 'https://github.com/puppetlabs/puppetlabs-puppet_agent.git'
+      ref: v4.12.1
     provision: 'https://github.com/puppetlabs/provision.git'
   symlinks:
     stdlib: "#{source_dir}"