diff --git a/recipes/README.recipes.md b/recipes/README.recipes.md
index 7d3b461c6..ad00a47fc 100644
--- a/recipes/README.recipes.md
+++ b/recipes/README.recipes.md
@@ -516,13 +516,13 @@ DEPRECATED. Consider using gerrit.get_change_description instead.
 — **def [upload](/recipes/recipe_modules/git_cl/api.py#47)(self, message, upload_args=None, \*\*kwargs):**
 ### *recipe_modules* / [gitiles](/recipes/recipe_modules/gitiles)
 
-[DEPS](/recipes/recipe_modules/gitiles/__init__.py#1): [recipe\_engine/json][recipe_engine/recipe_modules/json], [recipe\_engine/path][recipe_engine/recipe_modules/path], [recipe\_engine/python][recipe_engine/recipe_modules/python], [recipe\_engine/raw\_io][recipe_engine/recipe_modules/raw_io], [recipe\_engine/url][recipe_engine/recipe_modules/url]
+[DEPS](/recipes/recipe_modules/gitiles/__init__.py#5): [recipe\_engine/json][recipe_engine/recipe_modules/json], [recipe\_engine/path][recipe_engine/recipe_modules/path], [recipe\_engine/python][recipe_engine/recipe_modules/python], [recipe\_engine/raw\_io][recipe_engine/recipe_modules/raw_io], [recipe\_engine/step][recipe_engine/recipe_modules/step], [recipe\_engine/url][recipe_engine/recipe_modules/url]
 
 #### **class [Gitiles](/recipes/recipe_modules/gitiles/api.py#10)([RecipeApi][recipe_engine/wkt/RecipeApi]):**
 
 Module for polling a git repository using the Gitiles web interface.
 
-— **def [commit\_log](/recipes/recipe_modules/gitiles/api.py#102)(self, url, commit, step_name=None, attempts=None):**
+— **def [commit\_log](/recipes/recipe_modules/gitiles/api.py#113)(self, url, commit, step_name=None, attempts=None):**
 
 Returns: (dict) the Gitiles commit log structure for a given commit.
 
@@ -532,7 +532,23 @@ Args:
   step_name (str): If not None, override the step name.
   attempts (int): Number of times to try the request before failing.
 
-— **def [download\_file](/recipes/recipe_modules/gitiles/api.py#118)(self, repository_url, file_path, branch='master', step_name=None, attempts=None, \*\*kwargs):**
+— **def [download\_archive](/recipes/recipe_modules/gitiles/api.py#155)(self, repository_url, destination, revision='refs/heads/master'):**
+
+Downloads an archive of the repo and extracts it to `destination`.
+
+If the gitiles server attempts to provide a tarball with paths which escape
+`destination`, this function will extract all valid files and then
+raise StepFailure with an attribute `StepFailure.gitiles_skipped_files`
+containing the names of the files that were skipped.
+
+Args:
+  repository_url (str): Full URL to the repository
+  destination (Path): Local path to extract the archive to. Must not exist
+    prior to this call.
+  revision (str): The ref or revision in the repo to download. Defaults to
+    'refs/heads/master'.
+
+— **def [download\_file](/recipes/recipe_modules/gitiles/api.py#129)(self, repository_url, file_path, branch='master', step_name=None, attempts=None, \*\*kwargs):**
 
 Downloads raw file content from a Gitiles repository.
 
@@ -546,7 +562,7 @@ Args:
 Returns:
   Raw file content.
 
-— **def [log](/recipes/recipe_modules/gitiles/api.py#56)(self, url, ref, limit=0, cursor=None, step_name=None, attempts=None, \*\*kwargs):**
+— **def [log](/recipes/recipe_modules/gitiles/api.py#67)(self, url, ref, limit=0, cursor=None, step_name=None, attempts=None, \*\*kwargs):**
 
 Returns the most recent commits under the given ref with properties.
 
@@ -569,7 +585,7 @@ Returns:
   Cursor can be used for subsequent calls to log for paging. If None,
   signals that there are no more commits to fetch.
 
-— **def [refs](/recipes/recipe_modules/gitiles/api.py#44)(self, url, step_name='refs', attempts=None):**
+— **def [refs](/recipes/recipe_modules/gitiles/api.py#55)(self, url, step_name='refs', attempts=None):**
 
 Returns a list of refs in the remote repository.
 ### *recipe_modules* / [gsutil](/recipes/recipe_modules/gsutil)
@@ -778,9 +794,9 @@ like checkout or compile), and some of these tests have failed.
 — **def [RunSteps](/recipes/recipe_modules/git_cl/examples/full.py#17)(api):**
 ### *recipes* / [gitiles:examples/full](/recipes/recipe_modules/gitiles/examples/full.py)
 
-[DEPS](/recipes/recipe_modules/gitiles/examples/full.py#5): [gitiles](#recipe_modules-gitiles), [recipe\_engine/json][recipe_engine/recipe_modules/json], [recipe\_engine/properties][recipe_engine/recipe_modules/properties]
+[DEPS](/recipes/recipe_modules/gitiles/examples/full.py#5): [gitiles](#recipe_modules-gitiles), [recipe\_engine/json][recipe_engine/recipe_modules/json], [recipe\_engine/path][recipe_engine/recipe_modules/path], [recipe\_engine/properties][recipe_engine/recipe_modules/properties], [recipe\_engine/step][recipe_engine/recipe_modules/step]
 
-— **def [RunSteps](/recipes/recipe_modules/gitiles/examples/full.py#12)(api):**
+— **def [RunSteps](/recipes/recipe_modules/gitiles/examples/full.py#14)(api):**
 ### *recipes* / [gsutil:examples/full](/recipes/recipe_modules/gsutil/examples/full.py)
 
 [DEPS](/recipes/recipe_modules/gsutil/examples/full.py#5): [gsutil](#recipe_modules-gsutil), [recipe\_engine/path][recipe_engine/recipe_modules/path]
diff --git a/recipes/recipe_modules/gitiles/__init__.py b/recipes/recipe_modules/gitiles/__init__.py
index 16991642a..f8e8ca517 100644
--- a/recipes/recipe_modules/gitiles/__init__.py
+++ b/recipes/recipe_modules/gitiles/__init__.py
@@ -1,7 +1,12 @@
+# Copyright 2018 The Chromium Authors. All rights reserved.
+# Use of this source code is governed by a BSD-style license that can be
+# found in the LICENSE file.
+
 DEPS = [
     'recipe_engine/json',
     'recipe_engine/path',
     'recipe_engine/python',
     'recipe_engine/raw_io',
+    'recipe_engine/step',
     'recipe_engine/url',
 ]
diff --git a/recipes/recipe_modules/gitiles/api.py b/recipes/recipe_modules/gitiles/api.py
index c99957067..42c4086da 100644
--- a/recipes/recipe_modules/gitiles/api.py
+++ b/recipes/recipe_modules/gitiles/api.py
@@ -1,4 +1,4 @@
-# Copyright 2014 The Chromium Authors. All rights reserved.
+# Copyright 2018 The Chromium Authors. All rights reserved.
 # Use of this source code is governed by a BSD-style license that can be
 # found in the LICENSE file.
 
@@ -11,21 +11,33 @@ class Gitiles(recipe_api.RecipeApi):
   """Module for polling a git repository using the Gitiles web interface."""
 
   def _fetch(self, url, step_name, fmt, attempts=None, add_json_log=True,
-             log_limit=None, log_start=None, **kwargs):
+             log_limit=None, log_start=None, extract_to=None, **kwargs):
     """Fetches information from Gitiles.
 
     Arguments:
+      fmt (str): one of ('text', 'json', 'archive'). Instructs the underlying
+        gitiles_client tool how to process the HTTP response.
+          * text - implies the response is base64 encoded
+          * json - implies the response is JSON
+          * archive - implies the response is a compressed tarball; requires
+            `extract_to`.
+      extract_to (Path): When fmt=='archive', instructs gitiles_client to
+        extract the archive to this non-existant folder.
       log_limit: for log URLs, limit number of results. None implies 1 page,
         as returned by Gitiles.
       log_start: for log URLs, the start cursor for paging.
       add_json_log: if True, will spill out json into log.
     """
-    assert fmt in ('json', 'text')
+    assert fmt in ('json', 'text', 'archive')
+
     args = [
         '--json-file', self.m.json.output(add_json_log=add_json_log),
         '--url', url,
         '--format', fmt,
     ]
+    if fmt == 'archive':
+      assert extract_to is not None, 'archive format requires extract_to'
+      args.extend(['--extract-to', extract_to])
     if attempts:
       args.extend(['--attempts', attempts])
     if log_limit is not None:
@@ -37,9 +49,8 @@ class Gitiles(recipe_api.RecipeApi):
       args.extend([
           '--accept-statuses',
           ','.join([str(s) for s in accept_statuses])])
-    a = self.m.python(
+    return self.m.python(
         step_name, self.resource('gerrit_client.py'), args, **kwargs)
-    return a
 
   def refs(self, url, step_name='refs', attempts=None):
     """Returns a list of refs in the remote repository."""
@@ -140,3 +151,52 @@ class Gitiles(recipe_api.RecipeApi):
     if step_result.json.output['value'] is None:
       return None
     return base64.b64decode(step_result.json.output['value'])
+
+  def download_archive(self, repository_url, destination,
+                       revision='refs/heads/master'):
+    """Downloads an archive of the repo and extracts it to `destination`.
+
+    If the gitiles server attempts to provide a tarball with paths which escape
+    `destination`, this function will extract all valid files and then
+    raise StepFailure with an attribute `StepFailure.gitiles_skipped_files`
+    containing the names of the files that were skipped.
+
+    Args:
+      repository_url (str): Full URL to the repository
+      destination (Path): Local path to extract the archive to. Must not exist
+        prior to this call.
+      revision (str): The ref or revision in the repo to download. Defaults to
+        'refs/heads/master'.
+    """
+    step_name = 'download %s @ %s' % (repository_url, revision)
+    fetch_url = self.m.url.join(repository_url, '+archive/%s.tgz' % (revision,))
+    step_result = self._fetch(
+      fetch_url,
+      step_name,
+      fmt='archive',
+      add_json_log=False,
+      extract_to=destination,
+      step_test_data=lambda: self.m.json.test_api.output({
+        'extracted': {
+          'filecount': 1337,
+          'bytes': 7192345,
+        },
+      })
+    )
+    self.m.path.mock_add_paths(destination)
+    j = step_result.json.output
+    if j['extracted']['filecount']:
+      stat = j['extracted']
+      step_result.presentation.step_text += (
+        '<br/>extracted %s files - %.02f MB' % (
+          stat['filecount'], stat['bytes'] / (1000.0**2)))
+    if j.get('skipped', {}).get('filecount'):
+      stat = j['skipped']
+      step_result.presentation.step_text += (
+        '<br/>SKIPPED %s files - %.02f MB' % (
+          stat['filecount'], stat['bytes'] / (1000.0**2)))
+      step_result.presentation.logs['skipped files'] = stat['names']
+      step_result.presentation.status = self.m.step.FAILURE
+      ex = self.m.step.StepFailure(step_name)
+      ex.gitiles_skipped_files = stat['names']
+      raise ex
diff --git a/recipes/recipe_modules/gitiles/examples/full.expected/basic.json b/recipes/recipe_modules/gitiles/examples/full.expected/basic.json
index 568ee7643..17aba30dc 100644
--- a/recipes/recipe_modules/gitiles/examples/full.expected/basic.json
+++ b/recipes/recipe_modules/gitiles/examples/full.expected/basic.json
@@ -547,6 +547,49 @@
     ],
     "name": "fetch master:NONEXISTENT"
   },
+  {
+    "cmd": [
+      "python",
+      "-u",
+      "RECIPE_MODULE[depot_tools::gitiles]/resources/gerrit_client.py",
+      "--json-file",
+      "/path/to/tmp/json",
+      "--url",
+      "https://chromium.googlesource.com/chromium/src/+archive/refs/heads/master.tgz",
+      "--format",
+      "archive",
+      "--extract-to",
+      "[START_DIR]/archive"
+    ],
+    "name": "download https://chromium.googlesource.com/chromium/src @ refs/heads/master",
+    "~followup_annotations": [
+      "@@@STEP_TEXT@<br/>extracted 1337 files - 7.19 MB@@@"
+    ]
+  },
+  {
+    "cmd": [
+      "python",
+      "-u",
+      "RECIPE_MODULE[depot_tools::gitiles]/resources/gerrit_client.py",
+      "--json-file",
+      "/path/to/tmp/json",
+      "--url",
+      "https://chromium.googlesource.com/chromium/src/+archive/refs/heads/master.tgz",
+      "--format",
+      "archive",
+      "--extract-to",
+      "[START_DIR]/archive2"
+    ],
+    "name": "download https://chromium.googlesource.com/chromium/src @ refs/heads/master (2)",
+    "~followup_annotations": [
+      "@@@STEP_TEXT@<br/>extracted 10 files - 0.01 MB<br/>SKIPPED 4 files - 7.19 MB@@@",
+      "@@@STEP_LOG_LINE@skipped files@/root@@@",
+      "@@@STEP_LOG_LINE@skipped files@../relative@@@",
+      "@@@STEP_LOG_LINE@skipped files@sneaky/../../relative@@@",
+      "@@@STEP_LOG_END@skipped files@@@",
+      "@@@STEP_FAILURE@@@"
+    ]
+  },
   {
     "name": "$result",
     "recipe_result": null,
diff --git a/recipes/recipe_modules/gitiles/examples/full.py b/recipes/recipe_modules/gitiles/examples/full.py
index 6a249e54c..bb9df32bb 100644
--- a/recipes/recipe_modules/gitiles/examples/full.py
+++ b/recipes/recipe_modules/gitiles/examples/full.py
@@ -5,6 +5,8 @@
 DEPS = [
     'gitiles',
     'recipe_engine/json',
+    'recipe_engine/step',
+    'recipe_engine/path',
     'recipe_engine/properties',
 ]
 
@@ -22,6 +24,14 @@ def RunSteps(api):
   data = api.gitiles.download_file(url, 'NONEXISTENT', attempts=1,
                                    accept_statuses=[404])
 
+  api.gitiles.download_archive(url, api.path['start_dir'].join('archive'))
+
+  try:
+    api.gitiles.download_archive(url, api.path['start_dir'].join('archive2'))
+    assert False  # pragma: no cover
+  except api.step.StepFailure as ex:
+    assert '/root' in ex.gitiles_skipped_files
+
 
 def GenTests(api):
   yield (
@@ -65,4 +75,19 @@ def GenTests(api):
           'fetch master:NONEXISTENT',
           api.json.output({'value': None})
       )
+      + api.step_data(
+          ('download https://chromium.googlesource.com/chromium/src @ '
+           'refs/heads/master (2)'),
+        api.json.output({
+          'extracted': {
+            'filecount': 10,
+            'bytes': 14925,
+          },
+          'skipped': {
+            'filecount': 4,
+            'bytes': 7192345,
+            'names': ['/root', '../relative', 'sneaky/../../relative'],
+          },
+        })
+      )
   )
diff --git a/recipes/recipe_modules/gitiles/resources/gerrit_client.py b/recipes/recipe_modules/gitiles/resources/gerrit_client.py
index a34f23ce0..c38fc301d 100755
--- a/recipes/recipe_modules/gitiles/resources/gerrit_client.py
+++ b/recipes/recipe_modules/gitiles/resources/gerrit_client.py
@@ -15,6 +15,7 @@ import json
 import logging
 import os
 import sys
+import tarfile
 import time
 import urllib
 import urlparse
@@ -100,6 +101,16 @@ def main(arguments):
   parser = create_argparser()
   args = parser.parse_args(arguments)
 
+  if args.extract_to and args.format != "archive":
+    parser.error('--extract-to requires --format=archive')
+  if not args.extract_to and args.format == "archive":
+    parser.error('--format=archive requires --extract-to')
+
+  if args.extract_to:
+    # make sure it is absolute and ends with '/'
+    args.extract_to = os.path.join(os.path.abspath(args.extract_to), '')
+    os.makedirs(args.extract_to)
+
   parsed_url = urlparse.urlparse(args.url)
   if not parsed_url.scheme.startswith('http'):
     parser.error('Invalid URI scheme (expected http or https): %s' % args.url)
@@ -125,11 +136,49 @@ def main(arguments):
   elif args.format == 'text':
     # Text fetching will pack the text into structured JSON.
     def handler(conn):
-      result = ReadHttpResponse(conn, **kwargs).read()
       # Wrap in a structured JSON for export to recipe module.
       return {
-          'value': result or None,
+        'value': ReadHttpResponse(conn, **kwargs).read() or None,
       }
+  elif args.format == 'archive':
+    # Archive fetching hooks result to tarfile extraction. This implementation
+    # is able to do a streaming extraction operation without having to buffer
+    # the entire tarfile.
+    def handler(conn):
+      ret = {
+        'extracted': {
+          'filecount': 0,
+          'bytes': 0,
+        },
+        'skipped': {
+          'filecount': 0,
+          'bytes': 0,
+          'names': [],
+        }
+      }
+      fileobj = ReadHttpResponse(conn, **kwargs)
+      with tarfile.open(mode='r|*', fileobj=fileobj) as tf:
+        # monkeypatch the TarFile object to allow printing messages and
+        # collecting stats for each extracted file. extractall makes a single
+        # linear pass over the tarfile, which is compatible with
+        # ReadHttpResponse; other naive implementations (such as `getmembers`)
+        # do random access over the file and would require buffering the whole
+        # thing (!!).
+        em = tf._extract_member
+        def _extract_member(tarinfo, targetpath):
+          if not os.path.abspath(targetpath).startswith(args.extract_to):
+            print 'Skipping %s' % (tarinfo.name,)
+            ret['skipped']['filecount'] += 1
+            ret['skipped']['bytes'] += tarinfo.size
+            ret['skipped']['names'].append(tarinfo.name)
+            return
+          print 'Extracting %s' % (tarinfo.name,)
+          ret['extracted']['filecount'] += 1
+          ret['extracted']['bytes'] += tarinfo.size
+          return em(tarinfo, targetpath)
+        tf._extract_member = _extract_member
+        tf.extractall(args.extract_to)
+      return ret
 
   if args.log_start:
     query_params['s'] = args.log_start
@@ -158,10 +207,13 @@ def main(arguments):
 def create_argparser():
   parser = argparse.ArgumentParser()
   parser.add_argument(
-      '-j', '--json-file', required=True,
+      '-j', '--json-file',
       help='Path to json file for output.')
   parser.add_argument(
-      '-f', '--format', required=True, choices=('json', 'text'))
+      '--extract-to',
+      help='Local path to extract archive url. Must not exist.')
+  parser.add_argument(
+      '-f', '--format', required=True, choices=('json', 'text', 'archive'))
   parser.add_argument(
       '-u', '--url', required=True,
       help='Url of gitiles. For example, '