diff --git a/.fixtures.yml b/.fixtures.yml
index 4b983500..39cbdd00 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'
     stdlib: 'https://github.com/puppetlabs/puppetlabs-stdlib.git'
     mount_iso: 'https://github.com/puppetlabs/puppetlabs-mount_iso.git'