diff --git a/infra/act-runner-config.yml b/infra/act-runner-config.yml
index 9199a87..59636ed 100644
--- a/infra/act-runner-config.yml
+++ b/infra/act-runner-config.yml
@@ -8,6 +8,10 @@ log:
 runner:
   capacity: 2   # max concurrent jobs
   timeout: 30m
+  # Maps runs-on labels to Docker images for job containers.
+  # Change this (and delete /data/.runner) to switch the base image.
+  labels:
+    - "ubuntu-latest:docker://git.fabledsword.com/bvandeusen/runner-base:py3.12-node22"
 
 cache:
   enabled: true