--- a/testing/mozharness/mozharness/mozilla/building/buildbase.py
+++ b/testing/mozharness/mozharness/mozilla/building/buildbase.py
@@ -1626,32 +1626,22 @@ or run without that action (ie: --no-{ac
         if return_code:
             self.return_code = self.worst_level(
                 EXIT_STATUS_DICT[TBPL_FAILURE],  self.return_code,
                 AUTOMATION_EXIT_CODES[::-1]
             )
             self.fatal("'mach build' did not run successfully. Please check "
                        "log for errors.")
 
-    def _checkout_compare_locales(self):
-        dirs = self.query_abs_dirs()
-        dest = dirs['compare_locales_dir']
-        repo = self.config['compare_locales_repo']
-        rev = self.config['compare_locales_rev']
-        vcs = self.config['compare_locales_vcs']
-        abs_rev = self.vcs_checkout(repo=repo, dest=dest, revision=rev, vcs=vcs)
-        self.set_buildbot_property('compare_locales_revision', abs_rev, write_to_file=True)
-
     def multi_l10n(self):
         if not self.query_is_nightly():
             self.info("Not a nightly build, skipping multi l10n.")
             return
         self._initialize_taskcluster()
 
-        self._checkout_compare_locales()
         dirs = self.query_abs_dirs()
         base_work_dir = dirs['base_work_dir']
         objdir = dirs['abs_obj_dir']
         branch = self.buildbot_config['properties']['branch']
 
         # Some android versions share the same .json config - if
         # multi_locale_config_platform is set, use that the .json name;
         # otherwise, use the buildbot platform.

--- a/testing/mozharness/scripts/b2g_build.py
+++ b/testing/mozharness/scripts/b2g_build.py
@@ -49,17 +49,16 @@ class B2GBuild(LocalesMixin, PurgeMixin,
         'checkout-sources',
         # Deprecated
         'checkout-gecko',
         'download-gonk',
         'unpack-gonk',
         'checkout-gaia',
         'checkout-gaia-l10n',
         'checkout-gecko-l10n',
-        'checkout-compare-locales',
         # End deprecated
         'get-blobs',
         'update-source-manifest',
         'build',
         'build-symbols',
         'make-updates',
         'build-update-testdata',
         'prep-upload',
@@ -134,19 +133,16 @@ class B2GBuild(LocalesMixin, PurgeMixin,
             'ccache': True,
             'locales_dir': 'gecko/b2g/locales',
             'l10n_dir': 'gecko-l10n',
             'ignore_locales': ['en-US', 'multi'],
             'locales_file': 'gecko/b2g/locales/all-locales',
             'mozilla_dir': 'build/gecko',
             'objdir': 'build/objdir-gecko',
             'merge_locales': True,
-            'compare_locales_repo': 'https://hg.mozilla.org/build/compare-locales',
-            'compare_locales_rev': 'RELEASE_AUTOMATION',
-            'compare_locales_vcs': 'hg',
             'repo_remote_mappings': {},
             'influx_credentials_file': 'oauth.txt',
             'balrog_credentials_file': 'oauth.txt',
             'build_resources_path': '%(abs_obj_dir)s/.mozbuild/build_resources.json',
             'virtualenv_modules': [
                 'requests==2.8.1',
             ],
             'virtualenv_path': 'venv',
@@ -188,17 +184,16 @@ class B2GBuild(LocalesMixin, PurgeMixin,
     def query_abs_dirs(self):
         if self.abs_dirs:
             return self.abs_dirs
         abs_dirs = LocalesMixin.query_abs_dirs(self)
         abs_dirs.update(B2GBuildBaseScript.query_abs_dirs(self))
 
         dirs = {
             'gaia_l10n_base_dir': os.path.join(abs_dirs['abs_work_dir'], 'gaia-l10n'),
-            'compare_locales_dir': os.path.join(abs_dirs['abs_work_dir'], 'compare-locales'),
             'abs_public_upload_dir': os.path.join(abs_dirs['abs_work_dir'], 'upload-public'),
         }
 
         abs_dirs.update(dirs)
         self.abs_dirs = abs_dirs
         return self.abs_dirs
 
     def query_branch(self):
@@ -372,17 +367,16 @@ class B2GBuild(LocalesMixin, PurgeMixin,
                 dirs['abs_public_upload_dir'],
             ],
         )
 
     def checkout_sources(self):
         super(B2GBuild, self).checkout_sources()
         self.checkout_gecko_l10n()
         self.checkout_gaia_l10n()
-        self.checkout_compare_locales()
 
     def get_blobs(self):
         self.download_blobs()
         self.unpack_blobs()
 
     def download_blobs(self):
         dirs = self.query_abs_dirs()
         gecko_config = self.load_gecko_config()
@@ -427,25 +421,16 @@ class B2GBuild(LocalesMixin, PurgeMixin,
         # populate b2g/overrides, which isn't in gecko atm
         dirs = self.query_abs_dirs()
         for locale in gecko_locales:
             self.mkdir_p(os.path.join(dirs['abs_l10n_dir'], locale, 'b2g', 'chrome', 'overrides'))
             self.copytree(os.path.join(dirs['abs_l10n_dir'], locale, 'mobile', 'overrides'),
                           os.path.join(dirs['abs_l10n_dir'], locale, 'b2g', 'chrome', 'overrides'),
                           error_level=FATAL)
 
-    def checkout_compare_locales(self):
-        dirs = self.query_abs_dirs()
-        dest = dirs['compare_locales_dir']
-        repo = self.config['compare_locales_repo']
-        rev = self.config['compare_locales_rev']
-        vcs = self.config['compare_locales_vcs']
-        abs_rev = self.vcs_checkout(repo=repo, dest=dest, branch=rev, vcs=vcs)
-        self.set_buildbot_property('compare_locales_revision', abs_rev, write_to_file=True)
-
     def query_do_translate_hg_to_git(self, gecko_config_key=None):
         manifest_config = self.config.get('manifest', {})
         branch = self.query_branch()
         if self.query_is_nightly() and branch in manifest_config['branches'] and \
                 manifest_config.get('translate_hg_to_git'):
             if gecko_config_key is None:
                 return True
             if self.gecko_config.get(gecko_config_key):
@@ -585,19 +570,17 @@ class B2GBuild(LocalesMixin, PurgeMixin,
         if self.config.get('gaia_languages_file'):
             env['LOCALE_BASEDIR'] = dirs['gaia_l10n_base_dir']
             env['LOCALES_FILE'] = os.path.join(dirs['abs_work_dir'], 'gaia', self.config['gaia_languages_file'])
         if self.config.get('locales_file'):
             env['L10NBASEDIR'] = dirs['abs_l10n_dir']
             env['MOZ_CHROME_MULTILOCALE'] = " ".join(self.query_locales())
             if 'PATH' not in env:
                 env['PATH'] = os.environ.get('PATH')
-            env['PATH'] += ':%s' % os.path.join(dirs['compare_locales_dir'], 'scripts')
             env['PYTHONPATH'] = os.environ.get('PYTHONPATH', '')
-            env['PYTHONPATH'] += ':%s' % os.path.join(dirs['compare_locales_dir'], 'lib')
 
         with open(os.path.join(dirs['work_dir'], '.userconfig'), 'w') as cfg:
             cfg.write('GECKO_OBJDIR={0}'.format(self.objdir))
 
         self.enable_mock()
         if self.config['ccache']:
             self.run_command('ccache -z', cwd=dirs['work_dir'], env=env)
         for cmd in cmds:

--- a/testing/mozharness/scripts/fx_desktop_build.py
+++ b/testing/mozharness/scripts/fx_desktop_build.py
@@ -67,19 +67,16 @@ class FxDesktopBuild(BuildScript, object
                     "%(objdir)s/dist/fennec*",
                     "%(objdir)s/dist/seamonkey*",
                     "%(objdir)s/dist/thunderbird*",
                     "%(objdir)s/dist/install/sea/*.exe"
                 ],
                 'stage_product': 'firefox',
                 'platform_supports_post_upload_to_latest': True,
                 'latest_mar_dir': '/pub/mozilla.org/firefox/nightly/latest-%(branch)s',
-                'compare_locales_repo': 'https://hg.mozilla.org/build/compare-locales',
-                'compare_locales_rev': 'RELEASE_AUTOMATION',
-                'compare_locales_vcs': 'hgtool',
                 'influx_credentials_file': 'oauth.txt',
                 'build_resources_path': '%(abs_src_dir)s/obj-firefox/.mozbuild/build_resources.json',
                 'nightly_promotion_branches': ['mozilla-central', 'mozilla-aurora'],
 
                 # try will overwrite these
                 'clone_with_purge': False,
                 'clone_by_revision': False,
                 'tinderbox_build_dir': None,
@@ -149,17 +146,16 @@ class FxDesktopBuild(BuildScript, object
                                         'src',
                                         self._query_objdir()),
             'abs_tools_dir': os.path.join(abs_dirs['abs_work_dir'], 'tools'),
             'abs_app_ini_path': c['app_ini_path'] % {
                 'obj_dir': os.path.join(abs_dirs['abs_work_dir'],
                                         'src',
                                         self._query_objdir())
             },
-            'compare_locales_dir': os.path.join(abs_dirs['abs_work_dir'], 'compare-locales'),
         }
         abs_dirs.update(dirs)
         self.abs_dirs = abs_dirs
         return self.abs_dirs
 
         # Actions {{{2
         # read_buildbot_config in BuildingMixin
         # clobber in BuildingMixin -> PurgeMixin