--- a/taskcluster/ci/source-test/python.yml
+++ b/taskcluster/ci/source-test/python.yml
@@ -1,47 +1,44 @@
 job-defaults:
     platform: linux64/opt
     always-target: true
     worker-type:
         by-platform:
             linux64.*: aws-provisioner-v1/gecko-t-linux-xlarge
+    worker:
+        by-platform:
+            linux64.*:
+                docker-image: {in-tree: "lint"}
+                max-run-time: 3600
     treeherder:
         kind: test
         tier: 2
     run:
         using: mach
     when:
         files-changed:
             - 'config/mozunit.py'
             - 'python/mach_commands.py'
 
 taskgraph-tests:
     description: taskcluster/taskgraph unit tests
     treeherder:
         symbol: py(tg)
-    worker:
-        docker-image: {in-tree: "lint"}
-        max-run-time: 1800
     run:
         mach: python-test --subsuite taskgraph
     when:
         files-changed:
             - 'taskcluster/**/*.py'
             - 'python/mach/**/*.py'
 
 marionette-harness:
     description: testing/marionette/harness unit tests
     treeherder:
         symbol: py(mnh)
-    worker:
-        by-platform:
-            linux64.*:
-                docker-image: {in-tree: "lint"}
-                max-run-time: 3600
     run:
         mach: python-test --subsuite marionette-harness
     when:
         files-changed:
             - 'testing/marionette/harness/**'
             - 'testing/mozbase/mozlog/mozlog/**'
             - 'testing/mozbase/mozlog/setup.py'
             - 'testing/mozbase/packages.txt'
@@ -74,91 +71,62 @@ mochitest-harness:
             - 'testing/mozbase/moztest/moztest/selftest/**'
             - 'testing/mozharness/mozharness/base/log.py'
             - 'testing/mozharness/mozharness/mozilla/structuredlog.py'
             - 'testing/mozharness/mozharness/mozilla/testing/errors.py'
             - 'testing/profiles/prefs_general.js'
 
 mozbase:
     description: testing/mozbase unit tests
-    platform:
-        - linux64/opt
     treeherder:
         symbol: py(mb)
-    worker:
-        by-platform:
-            linux64.*:
-                docker-image: {in-tree: "lint"}
-                max-run-time: 3600
     run:
         mach: python-test --subsuite mozbase
     when:
         files-changed:
             - 'testing/mozbase/**'
 
 mozharness:
     description: mozharness integration tests
-    platform: linux64/opt
     treeherder:
         symbol: py(mh)
-    worker:
-        docker-image: {in-tree: "lint"}
-        max-run-time: 1800
     run:
         using: run-task
         cache-dotcache: true
         command: >
             cd /builds/worker/checkouts/gecko/testing/mozharness &&
             /usr/local/bin/tox -e py27-hg4.3
     when:
         files-changed:
             - 'testing/mozharness/**'
 
 mozlint:
     description: python/mozlint unit tests
-    platform: linux64/opt
     treeherder:
         symbol: py(ml)
-    worker:
-        by-platform:
-            linux64.*:
-                docker-image: {in-tree: "lint"}
-                max-run-time: 3600
     run:
         mach: python-test --subsuite mozlint
     when:
         files-changed:
             - 'python/mozlint/**'
 
 mozterm:
     description: python/mozterm unit tests
-    platform: linux64/opt
     treeherder:
         symbol: py(term)
-    worker:
-        by-platform:
-            linux64.*:
-                docker-image: {in-tree: "lint"}
-                max-run-time: 3600
     run:
         mach: python-test --subsuite mozterm
     when:
         files-changed:
             - 'python/mozterm/**'
 
 mozversioncontrol:
     description: python/mozversioncontrol unit tests
-    platform: linux64/opt
     treeherder:
         symbol: py(vcs)
-    worker:
-        by-platform:
-            linux64.*:
-                docker-image: {in-tree: "lint"}
-                max-run-time: 3600
     run:
         mach: python-test --subsuite mozversioncontrol
     when:
         files-changed:
             - 'python/mozversioncontrol/**'
 
 reftest-harness:
     description: layout/tools/reftest unittests