diff --git a/roles/run-test-command/tasks/main.yaml b/roles/run-test-command/tasks/main.yaml
index 1f16aa6..c195cca 100644
--- a/roles/run-test-command/tasks/main.yaml
+++ b/roles/run-test-command/tasks/main.yaml
@@ -2,3 +2,5 @@
   command: '{{ test_command }}'
   args:
     chdir: '{{ zuul.project.src_dir }}'
+  environment:
+    JOB_PERFORM_EXTRA_WORK: '{{ perform_extra_work | ternary("1", "0") }}'
diff --git a/zuul.yaml b/zuul.yaml
index 090d816..eaa0126 100644
--- a/zuul.yaml
+++ b/zuul.yaml
@@ -5,6 +5,7 @@
     run: playbooks/run-test-command/run.yaml
     vars:
       test_command: "ci/build.sh"
+      perform_extra_work: false
     nodeset:
       nodes:
         - name: w
@@ -26,6 +27,8 @@
     description: |
       Build on Fedora 29 with GCC.
     parent: run-ci-build-sh
+    vars:
+      perform_extra_work: true
 
 - job:
     name: f29-gcc-asan