diff --git a/infra/config/global/luci-scheduler.cfg b/infra/config/global/luci-scheduler.cfg
index 1b61b86..42d7e46 100644
--- a/infra/config/global/luci-scheduler.cfg
+++ b/infra/config/global/luci-scheduler.cfg
@@ -16,6 +16,8 @@
   }
 }
 
+# The format of this file is important, we have a hackish parsing to trigger
+# builds in tools/trigger.py
 trigger {
   id: "master-gitiles-trigger"
   acl_sets: "default"
diff --git a/tools/trigger.py b/tools/trigger.py
new file mode 100755
index 0000000..7f273e7
--- /dev/null
+++ b/tools/trigger.py
@@ -0,0 +1,82 @@
+#!/usr/bin/env python
+# Copyright (c) 2019, the R8 project authors. Please see the AUTHORS file
+# for details. All rights reserved. Use of this source code is governed by a
+# BSD-style license that can be found in the LICENSE file.
+
+# Convenience script for triggering bots on specific commits.
+
+import json
+import optparse
+import os
+import re
+import subprocess
+import sys
+import urllib
+
+import utils
+
+LUCI_SCHEDULE = os.path.join(utils.REPO_ROOT, 'infra', 'config', 'global',
+                             'luci-scheduler.cfg')
+# Trigger lines have the format:
+#   triggers: "BUILDER_NAME"
+TRIGGERS_RE = r'^  triggers: "(\w.*)"'
+
+def ParseOptions():
+  result = optparse.OptionParser()
+  result.add_option('--release',
+                    help='Run on the release branch builders.',
+                    default=False, action='store_true')
+  result.add_option('--builder', help='Trigger specific builder')
+  return result.parse_args()
+
+def get_builders():
+  is_release = False
+  master_builders = []
+  release_builders = []
+  with open(LUCI_SCHEDULE, 'r') as fp:
+    lines = fp.readlines()
+    for line in lines:
+      if 'branch-gitiles-trigger' in line:
+        is_release = True
+      match = re.match(TRIGGERS_RE, line)
+      if match:
+        builder = match.group(1)
+        if is_release:
+          assert 'release' in builder
+          release_builders.append(builder)
+        else:
+          assert 'release' not in builder
+          master_builders.append(builder)
+  print 'Master builders:\n  ' + '\n  '.join(master_builders)
+  print 'Release builders:\n  ' + '\n  '.join(release_builders)
+  return (master_builders, release_builders)
+
+def sanity_check_url(url):
+  a = urllib.urlopen(url)
+  if a.getcode() != 200:
+    raise Exception('Url: %s \n returned %s' % (url, a.getcode()))
+
+def trigger_builders(builders, commit):
+  commit_url = 'https://r8.googlesource.com/r8/+/%s' % commit
+  sanity_check_url(commit_url)
+  for builder in builders:
+    cmd = ['bb', 'add', 'r8/ci/%s' % builder , '-commit', commit_url]
+    subprocess.check_call(cmd)
+
+def Main():
+  (options, args) = ParseOptions()
+  if len(args) != 1:
+    print 'Takes exactly one argument, the commit to run'
+    return 1
+  commit = args[0]
+  (master_builders, release_builders) = get_builders()
+  if options.builder:
+    builder = options.builder
+    assert builder in master_builders or builder in release_builders
+    trigger_builders([builder], commit)
+  else:
+    trigger_builders(release_builders if options.release else master_builders,
+                     commit)
+
+if __name__ == '__main__':
+  sys.exit(Main())