--- a/.hgignore
+++ b/.hgignore
@@ -140,16 +140,21 @@ GPATH
 ^testing/talos/talos/tests/tp5n
 ^testing/talos/talos/tests/devtools/damp.manifest.develop
 ^talos-venv
 ^py3venv
 ^testing/talos/talos/mitmproxy/mitmdump
 ^testing/talos/talos/mitmproxy/mitmproxy
 ^testing/talos/talos/mitmproxy/mitmweb
 
+# Ignore talos speedometer files; source is copied from in-tree /third_party
+# into testing/talos/talos/tests/webkit/PerformanceTests/Speedometer when
+# talos speedometer test is run locally
+^testing/talos/talos/tests/webkit/PerformanceTests/Speedometer
+
 # Ignore toolchains.json created by tooltool.
 ^toolchains\.json
 
 # Ignore files created when running a reftest.
 ^lextab.py$
 
 # tup database
 ^\.tup

--- a/testing/mozharness/mozharness/mozilla/testing/talos.py
+++ b/testing/mozharness/mozharness/mozilla/testing/talos.py
@@ -412,16 +412,36 @@ class Talos(TestingMixin, MercurialScrip
                 )
                 archive = os.path.join(src_talos_pageset, self.pagesets_name)
                 unzip = self.query_exe('unzip')
                 unzip_cmd = [unzip, '-q', '-o', archive, '-d', src_talos_pageset]
                 self.run_command(unzip_cmd, halt_on_failure=True)
             else:
                 self.info("Not downloading pageset because the no-download option was specified")
 
+        # if running speedometer locally, need to copy speedometer source into talos/tests
+        if self.config.get('run_local') and 'speedometer' in self.suite:
+            self.get_speedometer_source()
+
+    def get_speedometer_source(self):
+        # in production the build system auto copies speedometer source into place;
+        # but when run locally we need to do this manually, so that talos can find it
+        src = os.path.join(self.repo_path, 'third_party', 'webkit',
+                                 'PerformanceTests', 'Speedometer')
+        dest = os.path.join(self.talos_path, 'talos', 'tests', 'webkit',
+                                      'PerformanceTests', 'Speedometer')
+        if not os.path.exists(dest):
+            self.info("Copying speedometer source from %s to %s" % (src, dest))
+            try:
+                shutil.copytree(src, dest)
+            except:
+                self.critical("Error copying speedometer source from %s to %s" % (src, dest))
+        else:
+            self.info("Speedometer source already found at %s" % dest)
+
     def setup_mitmproxy(self):
         """Some talos tests require the use of mitmproxy to playback the pages,
         set it up here.
         """
         if not self.query_mitmproxy_recording_set():
             self.info("Skipping: mitmproxy is not required")
             return