--- a/mozilla/config.py
+++ b/mozilla/config.py
@@ -925,16 +925,17 @@ PLATFORM_VARS = {
                 ('/builds/crash-stats-api.token', '/builds/crash-stats-api.token'),
                 ('/usr/local/lib/hgext', '/usr/local/lib/hgext'),
             ],
         },
         'macosx64': {
             'mozharness_python': '/tools/buildbot/bin/python',
             'reboot_command': ['scripts/external_tools/count_and_reboot.py',
                                '-f', '../reboot_count.txt', '-n', '1', '-z'],
+            'tools_repo_cache': '/tools/checkouts/build-tools',
             'mozharness_desktop_build': {
                 'script_name': 'scripts/fx_desktop_build.py',
                 'extra_args': [
                     '--config', 'builds/releng_base_mac_64_builds.py',
                     '--config', GLOBAL_VARS['mozharness_configs']['balrog'],
                 ],
                 'script_timeout': 3 * 3600,
                 'script_maxtime': int(5.5 * 3600),
@@ -1341,16 +1342,17 @@ PLATFORM_VARS = {
                 ('/builds/crash-stats-api.token', '/builds/crash-stats-api.token'),
                 ('/usr/local/lib/hgext', '/usr/local/lib/hgext'),
             ],
         },
         'macosx64-debug': {
             'mozharness_python': '/tools/buildbot/bin/python',
             'reboot_command': ['scripts/external_tools/count_and_reboot.py',
                                '-f', '../reboot_count.txt', '-n', '1', '-z'],
+            'tools_repo_cache': '/tools/checkouts/build-tools',
             'mozharness_desktop_build': {
                 'script_name': 'scripts/fx_desktop_build.py',
                 'extra_args': [
                     '--config', 'builds/releng_base_mac_64_builds.py',
                     '--custom-build-variant-cfg', 'debug',
                     '--config', GLOBAL_VARS['mozharness_configs']['balrog'],
                 ],
                 'script_timeout': 3 * 3600,
@@ -1398,16 +1400,17 @@ PLATFORM_VARS = {
             'dep_signing_servers': 'dep-signing',
             'tooltool_manifest_src': 'browser/config/tooltool-manifests/macosx64/releng.manifest',
             'enable_ccache': True,
         },
         'macosx64-st-an-debug': {
             'mozharness_python': '/tools/buildbot/bin/python',
             'reboot_command': ['scripts/external_tools/count_and_reboot.py',
                                '-f', '../reboot_count.txt', '-n', '1', '-z'],
+            'tools_repo_cache': '/tools/checkouts/build-tools',
             'mozharness_desktop_build': {
                 'script_name': 'scripts/fx_desktop_build.py',
                 'extra_args': [
                     '--config', 'builds/releng_base_mac_64_builds.py',
                     '--custom-build-variant-cfg', 'stat-and-debug',
                     '--config', GLOBAL_VARS['mozharness_configs']['balrog'],
                 ],
                 'script_timeout': 3 * 3600,