--- a/taskcluster/ci/build/macosx.yml
+++ b/taskcluster/ci/build/macosx.yml
@@ -38,16 +38,37 @@ macosx64/opt:
         actions: [get-secrets build update]
         config:
             - builds/releng_base_mac_64_builds.py
             - balrog/production.py
         script: "mozharness/scripts/fx_desktop_build.py"
         secrets: true
         tooltool-downloads: internal
 
+macosx64-yosemite/opt:
+    description: "MacOS X 10.10 x64"
+    index:
+        product: firefox
+        job-name: macosx64-yosemite-opt
+    treeherder:
+        platform: osx-10-10/opt
+        symbol: tc(B)
+        tier: 2
+    worker-type: buildbot-bridge/buildbot-bridge
+    run:
+        using: mozharness
+        actions: [get-secrets build update]
+        config:
+            - builds/releng_base_mac_64_builds.py
+            - balrog/production.py
+        script: "mozharness/scripts/fx_desktop_build.py"
+        secrets: true
+        tooltool-downloads: internal
+    run-on-projects: []
+
 macosx64-noopt/debug:
     description: "MacOS X x64 No-optimize Debug"
     index:
         product: firefox
         job-name: macosx64-noopt-debug
     treeherder:
         platform: osx-10-7-noopt/debug
         symbol: tc(B)

--- a/taskcluster/taskgraph/transforms/gecko_v2_whitelist.py
+++ b/taskcluster/taskgraph/transforms/gecko_v2_whitelist.py
@@ -51,16 +51,17 @@ JOB_NAME_WHITELIST = set([
     'linux64-valgrind-opt',
     'macosx64-add-on-devel',
     'macosx64-clang-tidy',
     'macosx64-debug',
     'macosx64-noopt-debug',
     'macosx64-opt',
     'macosx64-st-an-debug',
     'macosx64-st-an-opt',
+    'macosx64-yosemite-opt',
     'shell-haz-debug',
     'sm-arm-sim-debug',
     'sm-arm64-sim-debug',
     'sm-asan-opt',
     'sm-compacting-debug',
     'sm-fuzzing',
     'sm-mozjs-sys-debug',
     'sm-msan-opt',

--- a/taskcluster/taskgraph/transforms/job/mozharness.py
+++ b/taskcluster/taskgraph/transforms/job/mozharness.py
@@ -255,18 +255,23 @@ def mozharness_on_generic_worker(config,
 def mozharness_on_buildbot_bridge(config, job, taskdesc):
     run = job['run']
     worker = taskdesc['worker']
     branch = config.params['project']
     product = run.get('index', {}).get('product', 'firefox')
 
     worker.pop('env', None)
 
+    if 'yosemite' in job['attributes']['build_platform']:
+        buildername = 'OS X 10.10 {} build'.format(branch)
+    else:
+        buildername = 'OS X 10.7 {} build'.format(branch)
+
     worker.update({
-        'buildername': 'OS X 10.7 {} build'.format(branch),
+        'buildername': buildername,
         'sourcestamp': {
             'branch': branch,
             'repository': config.params['head_repository'],
             'revision': config.params['head_rev'],
         },
         'properties': {
             'product': product,
             'who': config.params['owner'],