diff --git a/etc/taskcluster/decision_task.py b/etc/taskcluster/decision_task.py
index 408e9dab21f..e9a3c2e443e 100644
--- a/etc/taskcluster/decision_task.py
+++ b/etc/taskcluster/decision_task.py
@@ -637,7 +637,7 @@ def macos_wpt():
         build_task,
         repo_dir="repo",
         repo_kwargs=dict(alternate_object_dir="/var/cache/servo.git/objects"),
-        total_chunks=6,
+        total_chunks=30,
         processes=4,
     )