diff --git a/base/BUILD.gn b/base/BUILD.gn
index 238a89a78fb3d5ebb2bcd92c3ff97bb10475daca..c01bb88d4579bcaf7245f50367c10e04030b8733 100644
--- a/base/BUILD.gn
+++ b/base/BUILD.gn
@@ -11,6 +11,11 @@ if (is_android) {
 
 config("base_implementation") {
   defines = [ "BASE_IMPLEMENTATION" ]
+
+  if (is_ios) {
+    # base uses routines deprecated in iOS 8
+    cflags = [ "-Wno-deprecated-declarations" ]
+  }
 }
 
 if (is_win) {
@@ -799,11 +804,6 @@ component("base") {
       "threading/platform_thread_internal_posix.cc",
     ]
 
-    if (is_asan) {
-      # TODO(GYP) hook up asan on Mac. GYP has this extra dylib:
-      #data += [ "$root_out_dir/libclang_rt.asan_osx_dynamic.dylib" ]
-    }
-
     if (is_ios) {
       sources -= [
         "files/file_path_watcher_fsevents.cc",
diff --git a/build/config/BUILD.gn b/build/config/BUILD.gn
index 287a1e762b52e84c1d114dca794af45e6a353e6c..e313d21a164fe840424efb07d7a4cf11c97e592a 100644
--- a/build/config/BUILD.gn
+++ b/build/config/BUILD.gn
@@ -386,14 +386,16 @@ config("default_libs") {
       "Foundation.framework",
       "IOKit.framework",
       "Security.framework",
+      "OpenGL.framework",
     ]
   } else if (is_ios) {
+    # The libraries listed here will be specified for both the target and the
+    # host. Only the common ones should be listed here.
     libs = [
       "CoreFoundation.framework",
       "CoreGraphics.framework",
       "CoreText.framework",
       "Foundation.framework",
-      "UIKit.framework",
     ]
   } else if (is_linux) {
     libs = [ "dl" ]
diff --git a/build/config/BUILDCONFIG.gn b/build/config/BUILDCONFIG.gn
index 5822d61a06f80a99575f6e99886b637e85d439c2..2e39c830d827cac17cfb084e07ad52f9c777b5d4 100644
--- a/build/config/BUILDCONFIG.gn
+++ b/build/config/BUILDCONFIG.gn
@@ -579,7 +579,7 @@ if (is_win) {
   set_default_toolchain(host_toolchain)
 } else if (is_ios) {
   host_toolchain = "//build/toolchain/mac:clang_x64"
-  set_default_toolchain("//build/toolchain/mac:clang_$current_cpu")
+  set_default_toolchain("//build/toolchain/mac:ios_clang_arm")
 } else if (is_nacl) {
   # TODO(GYP): This will need to change when we get NaCl working
   # on multiple platforms, but this whole block of code (how we define
diff --git a/build/config/compiler/BUILD.gn b/build/config/compiler/BUILD.gn
index 140e32936083c368169b14962e57a200389a4309..807f201340d135704bbad3c8b7e2d52848bad906 100644
--- a/build/config/compiler/BUILD.gn
+++ b/build/config/compiler/BUILD.gn
@@ -260,7 +260,7 @@ config("compiler") {
     } else if (current_cpu == "arm") {
       common_mac_flags += [
         "-arch",
-        "armv7",
+        "arm64",
       ]
     }
 
diff --git a/build/config/ios/BUILD.gn b/build/config/ios/BUILD.gn
index 0539810f818dd46564a57cff05e4ca1a5723bd48..b77df7956117bf16ab25831185c19c723f8bbfaa 100644
--- a/build/config/ios/BUILD.gn
+++ b/build/config/ios/BUILD.gn
@@ -6,17 +6,4 @@ import("//build/config/sysroot.gni")
 import("//build/config/ios/ios_sdk.gni")
 
 config("sdk") {
-  common_flags = [
-    "-isysroot",
-    sysroot,
-  ]
-
-  if (use_ios_simulator) {
-    common_flags += [ "-mios-simulator-version-min=$ios_deployment_target" ]
-  } else {
-    common_flags += [ "-miphoneos-version-min=$ios_deployment_target" ]
-  }
-
-  cflags = common_flags
-  ldflags = common_flags
 }
diff --git a/build/config/ios/find_signing_identity.py b/build/config/ios/find_signing_identity.py
new file mode 100644
index 0000000000000000000000000000000000000000..39355c054792fd1f565d45d4009d94c2ba090a67
--- /dev/null
+++ b/build/config/ios/find_signing_identity.py
@@ -0,0 +1,36 @@
+#!/usr/bin/python
+# Copyright (c) 2015 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.
+
+import subprocess
+import sys
+import re
+
+def ListIdentities():
+  return subprocess.check_output([
+    '/usr/bin/env',
+    'xcrun',
+    'security',
+    'find-identity',
+    '-v',
+    '-p',
+    'codesigning',
+  ]).strip()
+
+
+def FindValidIdentity():
+  lines = ListIdentities().splitlines()
+  # Look for something like "2) XYZ "iPhone Developer: Name (ABC)""
+  exp = re.compile('.*\) ([A-F|0-9]*)(.*)')
+  for line in lines:
+    res = exp.match(line)
+    if res is None:
+      continue
+    if "iPhone Developer" in res.group(2):
+      return res.group(1)
+  return ""
+
+
+if __name__ == '__main__':
+  print FindValidIdentity()
diff --git a/build/config/ios/ios_app.py b/build/config/ios/ios_app.py
new file mode 100644
index 0000000000000000000000000000000000000000..fa86c7acf17fe5039ba169f79e236d429034c1a7
--- /dev/null
+++ b/build/config/ios/ios_app.py
@@ -0,0 +1,110 @@
+#!/usr/bin/python
+# Copyright (c) 2015 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.
+
+import argparse
+import os
+import errno
+import subprocess
+import sys
+
+PLUTIL = [
+  '/usr/bin/env',
+  'xcrun',
+  'plutil'
+]
+
+
+def ProcessInfoPlist(args):
+  output_plist_file = os.path.abspath(os.path.join(args.output, 'Info.plist'))
+  return subprocess.check_call( PLUTIL + [
+    '-convert',
+    'binary1',
+    '-o',
+    output_plist_file,
+    '--',
+    args.input,
+  ])
+
+
+def PerformCodeSigning(args):
+  return subprocess.check_call([
+    '/usr/bin/env',
+    'xcrun',
+    'codesign',
+    '--entitlements',
+    args.entitlements_path,
+    '--sign',
+    args.identity,
+    '-f',
+    args.application_path,
+  ])
+
+
+def MakeDirectories(path):
+  try:
+    os.makedirs(path)
+  except OSError as exc:
+    if exc.errno == errno.EEXIST and os.path.isdir(path):
+      return 0
+    else:
+      return -1
+
+  return 0
+
+
+def GenerateProjectStructure(args):
+  application_path = os.path.join( args.dir, args.name + ".app" )
+  return MakeDirectories( application_path )
+
+
+def Main():
+  parser = argparse.ArgumentParser(description='A script that aids in '
+                                   'the creation of an iOS application')
+
+  subparsers = parser.add_subparsers()
+
+  # Plist Parser
+
+  plist_parser = subparsers.add_parser('plist',
+                                       help='Process the Info.plist')
+  plist_parser.set_defaults(func=ProcessInfoPlist)
+  
+  plist_parser.add_argument('-i', dest='input', help='The input plist path')
+  plist_parser.add_argument('-o', dest='output', help='The output plist dir')
+
+  # Directory Structure Parser
+
+  dir_struct_parser = subparsers.add_parser('structure',
+                      help='Creates the directory of an iOS application')
+
+  dir_struct_parser.set_defaults(func=GenerateProjectStructure)
+
+  dir_struct_parser.add_argument('-d', dest='dir', help='Out directory')
+  dir_struct_parser.add_argument('-n', dest='name', help='App name')
+
+  # Code Signing
+
+  code_signing_parser = subparsers.add_parser('codesign',
+                        help='Code sign the specified application')
+
+  code_signing_parser.set_defaults(func=PerformCodeSigning)
+
+  code_signing_parser.add_argument('-p', dest='application_path', required=True,
+                                   help='The application path')
+  code_signing_parser.add_argument('-i', dest='identity', required=True,
+                                   help='The code signing identity to use')
+  code_signing_parser.add_argument('-e', dest='entitlements_path',
+                                   required=True,
+                                   help='The path to the entitlements .xcent')
+
+  # Engage!
+
+  args = parser.parse_args()
+  
+  return args.func(args)
+
+
+if __name__ == '__main__':
+  sys.exit(Main())
diff --git a/build/config/ios/ios_sdk.gni b/build/config/ios/ios_sdk.gni
index cb2708b76c107d329bf17c5611fbbcd76aa713b3..1cb3a310207029ba0fb46fb6c4bab4fcdeae5207 100644
--- a/build/config/ios/ios_sdk.gni
+++ b/build/config/ios/ios_sdk.gni
@@ -1,4 +1,4 @@
-# Copyright 2014 The Chromium Authors. All rights reserved.
+# Copyright 2015 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.
 
@@ -15,6 +15,9 @@ declare_args() {
 
   # Version of iOS that we're targeting.
   ios_deployment_target = "6.0"
+
+  # The iOS Code signing identity to use
+  ios_code_signing_identity = ""
 }
 
 if (ios_sdk_path == "") {
@@ -28,3 +31,22 @@ if (ios_sdk_path == "") {
       exec_script("ios_sdk.py", [ _ios_sdk_to_query ], "list lines")
   ios_sdk_path = _ios_sdk_result[0]
 }
+
+if (use_ios_simulator) {
+  # Always disable code signing on the simulator
+  ios_code_signing_identity = ""
+} else {
+  # If an identity is not provided, look for one on the host
+  if (ios_code_signing_identity == "") {
+    _ios_identities = exec_script("find_signing_identity.py", 
+                                  [], "list lines")
+    ios_code_signing_identity = _ios_identities[0]
+  }
+
+  if (ios_code_signing_identity == "") {
+    print("Tried to prepare a device build without specifying a code signing")
+    print("identity and could not detect one automatically either.")
+    print("TIP: Simulator builds dont require code signing...")
+    assert(false)
+  }
+}
diff --git a/build/config/ios/ios_sim.py b/build/config/ios/ios_sim.py
new file mode 100755
index 0000000000000000000000000000000000000000..e56fd6e5788fcbc7fd5bf33066296d00c32b62ec
--- /dev/null
+++ b/build/config/ios/ios_sim.py
@@ -0,0 +1,108 @@
+#!/usr/bin/python
+# Copyright (c) 2015 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.
+
+import argparse
+import os
+import errno
+import subprocess
+import sys
+import re
+
+SIMCTL_PATH = [
+  '/usr/bin/env',
+  'xcrun',
+  'simctl',
+]
+
+PLIST_BUDDY_PATH = [
+  '/usr/bin/env',
+  'xcrun',
+  'PlistBuddy',
+]
+
+
+def ApplicationIdentifier(path):
+  identifier = subprocess.check_output( PLIST_BUDDY_PATH + [
+    '-c',
+    'Print CFBundleIdentifier',
+    '%s/Info.plist' % path,
+  ])
+
+  return identifier.strip()
+
+
+def Install(args):
+  return subprocess.check_call( SIMCTL_PATH + [
+    'install',
+    'booted',
+    args.path,
+  ])
+
+
+def InstallLaunchAndWait(args, wait):
+  res = Install(args)
+
+  if res != 0:
+    return res
+
+  identifier = ApplicationIdentifier(args.path)
+
+  launch_args = [ 'launch' ]
+
+  if wait:
+    launch_args += [ '-w' ]
+
+  launch_args += [
+    'booted',
+    identifier,
+  ]
+
+  return subprocess.check_output( SIMCTL_PATH + launch_args ).strip()
+
+
+def Launch(args):
+  InstallLaunchAndWait(args, False)
+
+
+def Debug(args):
+  launch_res = InstallLaunchAndWait(args, True)
+  launch_pid = re.search('.*: (\d+)', launch_res).group(1)
+  return os.system(' '.join([
+    '/usr/bin/env',
+    'xcrun',
+    'lldb',
+    '-s',
+    os.path.join(os.path.dirname(__file__), 'lldb_start_commands.txt'),
+    '-p',
+    launch_pid,
+  ]))
+
+
+def Main():
+  parser = argparse.ArgumentParser(description='A script that launches an'
+                                   ' application in the simulator and attaches'
+                                   ' the debugger to the same')
+
+  parser.add_argument('-p', dest='path', required=True,
+                      help='Path the the simulator application')
+
+  subparsers = parser.add_subparsers()
+
+  launch_parser = subparsers.add_parser('launch', help='Launch')
+  launch_parser.set_defaults(func=Launch)
+
+  install_parser = subparsers.add_parser('install', help='Install')
+  install_parser.set_defaults(func=Install)
+
+  debug_parser = subparsers.add_parser('debug', help='Debug')
+  debug_parser.set_defaults(func=Debug)
+
+  args = parser.parse_args()
+
+  return args.func(args)
+
+
+if __name__ == '__main__':
+  sys.exit(Main())
diff --git a/build/config/ios/lldb_start_commands.txt b/build/config/ios/lldb_start_commands.txt
new file mode 100644
index 0000000000000000000000000000000000000000..42e0b14c747db8f77ce9831121b754b1403d05bb
--- /dev/null
+++ b/build/config/ios/lldb_start_commands.txt
@@ -0,0 +1,4 @@
+breakpoint set --name UIApplicationMain
+breakpoint set --name objc_exception_throw
+continue
+script print "........ Debugger break on main() ........"
diff --git a/build/config/ios/rules.gni b/build/config/ios/rules.gni
new file mode 100644
index 0000000000000000000000000000000000000000..003226287b79adfdc78977dfc838f7bd78a74f72
--- /dev/null
+++ b/build/config/ios/rules.gni
@@ -0,0 +1,172 @@
+# Copyright 2015 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.
+
+ios_app_script = "//build/config/ios/ios_app.py"
+
+template("code_sign_ios") {
+  assert(defined(invoker.entitlements_path),
+         "The path to the entitlements .xcent file")
+  assert(defined(invoker.identity),
+         "The code signing identity")
+  assert(defined(invoker.application_path),
+         "The application to code sign")
+  assert(defined(invoker.deps))
+
+  action(target_name) {
+    sources = [
+      invoker.entitlements_path,
+    ]
+
+    _application_path = invoker.application_path
+
+    script = ios_app_script
+
+    outputs = [
+      "$_application_path/_CodeSignature/CodeResources"
+    ]
+
+    args = [
+      "codesign",
+      "-p",
+      rebase_path(invoker.application_path, root_build_dir),
+      "-i",
+      invoker.identity,
+      "-e",
+      rebase_path(invoker.entitlements_path, root_build_dir),
+    ]
+
+    deps = invoker.deps
+  }
+}
+
+template("resource_copy_ios") {
+  assert(defined(invoker.resources),
+         "The source list of resources to copy over")
+  assert(defined(invoker.bundle_directory),
+         "The directory within the bundle to place the sources in")
+  assert(defined(invoker.app_name),
+         "The name of the application")
+
+  _bundle_directory = invoker.bundle_directory
+  _app_name = invoker.app_name
+  _resources = invoker.resources
+
+  copy(target_name) {
+    set_sources_assignment_filter([])
+    sources = _resources
+    outputs = [ "$root_build_dir/$_app_name.app/$_bundle_directory/{{source_file_part}}" ]
+  }
+}
+
+template("ios_app") {
+
+  assert(defined(invoker.deps),
+         "Dependencies must be specified for $target_name")
+  assert(defined(invoker.info_plist),
+         "The application plist file must be specified for $target_name")
+  assert(defined(invoker.app_name),
+         "The name of iOS application for $target_name")
+  assert(defined(invoker.entitlements_path),
+         "The entitlements path must be specified for $target_name")
+  assert(defined(invoker.code_signing_identity),
+         "The entitlements path must be specified for $target_name")
+
+  # We just create a variable so we can use the same in interpolation
+  app_name = invoker.app_name
+
+  # Generate the project structure
+
+  struct_gen_target_name = target_name + "_struct"
+
+  action(struct_gen_target_name) {
+
+    script = ios_app_script
+
+    sources = []
+    outputs = [ "$root_build_dir/$app_name.app" ]
+
+    args = [
+      "structure",
+      "-d",
+      rebase_path(root_build_dir),
+      "-n",
+      app_name
+    ]
+
+  }
+
+  # Generate the executable
+
+  bin_gen_target_name = target_name + "_bin"
+
+  executable(bin_gen_target_name) {
+    libs = [ "UIKit.framework", "QuartzCore.framework", "OpenGLES.framework" ]
+    deps = invoker.deps
+    output_name = app_name
+  }
+
+  # Process the Info.plist
+
+  plist_gen_target_name = target_name + "_plist"
+
+  action(plist_gen_target_name) {
+
+    script = ios_app_script
+
+    sources = [ invoker.info_plist ]
+    outputs = [ "$root_build_dir/Info.plist" ]
+
+    args = [
+      "plist",
+      "-i",
+      rebase_path(invoker.info_plist, root_build_dir),
+      "-o",
+      rebase_path(root_build_dir),
+    ]
+  }
+
+  # Copy the generated binaries and assets to their appropriate locations
+
+  copy_gen_target_name = target_name + "_copy"
+  copy(copy_gen_target_name) {
+    sources = [
+      "$root_build_dir/Info.plist",
+      "$root_build_dir/$app_name",
+    ]
+
+    outputs = [
+      "$root_build_dir/$app_name.app/{{source_file_part}}"
+    ]
+
+    deps = [
+      ":$struct_gen_target_name",
+      ":$bin_gen_target_name",
+      ":$plist_gen_target_name",
+    ]
+  }
+
+  # Perform Code Signing
+
+  code_sign_gen_target_name = target_name + "_codesign"
+  code_sign_ios(code_sign_gen_target_name) {
+    entitlements_path = invoker.entitlements_path
+    identity = invoker.code_signing_identity
+    application_path = "$root_build_dir/$app_name.app"
+    deps = [ ":$copy_gen_target_name" ]
+  }
+
+  # Top level group
+
+  group(target_name) {
+    # Skip code signing if no identity is provided. This is useful for simulator
+    # builds
+    deps = []
+    if (invoker.code_signing_identity == "") {
+      deps += [ ":$copy_gen_target_name" ]
+    } else {
+      deps += [ ":$code_sign_gen_target_name" ]
+    }
+  }
+
+}
diff --git a/build/config/mac/BUILD.gn b/build/config/mac/BUILD.gn
index 9288add13952d3ba3ee0d4fac2019ae510761824..128ba025c8cdde47d5b157e200eed3bb83050c1f 100644
--- a/build/config/mac/BUILD.gn
+++ b/build/config/mac/BUILD.gn
@@ -8,7 +8,8 @@ config("sdk") {
   common_flags = [
     "-isysroot",
     sysroot,
-    "-mmacosx-version-min=10.6",
+    "-mmacosx-version-min=$mac_sdk_min",
+    "-stdlib=libc++",
   ]
 
   cflags = common_flags
diff --git a/build/config/mac/mac_app.py b/build/config/mac/mac_app.py
new file mode 100644
index 0000000000000000000000000000000000000000..909fa583e641581186bfd749059025323fadf1b5
--- /dev/null
+++ b/build/config/mac/mac_app.py
@@ -0,0 +1,113 @@
+#!/usr/bin/python
+# Copyright (c) 2015 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.
+
+import argparse
+import os
+import errno
+import subprocess
+import sys
+
+PLUTIL = [
+  '/usr/bin/env',
+  'xcrun',
+  'plutil'
+]
+
+IBTOOL = [
+  '/usr/bin/env',
+  'xcrun',
+  'ibtool',
+]
+
+
+def MakeDirectories(path):
+  try:
+    os.makedirs(path)
+  except OSError as exc:
+    if exc.errno == errno.EEXIST and os.path.isdir(path):
+      return 0
+    else:
+      return -1
+
+  return 0
+
+
+def ProcessInfoPlist(args):
+  output_plist_file = os.path.abspath(os.path.join(args.output, 'Info.plist'))
+  return subprocess.check_call( PLUTIL + [
+    '-convert',
+    'binary1',
+    '-o',
+    output_plist_file,
+    '--',
+    args.input,
+  ])
+
+
+def ProcessNIB(args):
+  output_nib_file = os.path.join(os.path.abspath(args.output),
+      "%s.nib" % os.path.splitext(os.path.basename(args.input))[0])
+
+  return subprocess.check_call(IBTOOL + [
+    '--module',
+    args.module,
+    '--auto-activate-custom-fonts',
+    '--target-device',
+    'mac',
+    '--compile',
+    output_nib_file,
+    os.path.abspath(args.input),
+  ])
+
+
+def GenerateProjectStructure(args):
+  application_path = os.path.join( args.dir, args.name + ".app", "Contents" )
+  return MakeDirectories( application_path )
+
+
+def Main():
+  parser = argparse.ArgumentParser(description='A script that aids in '
+                                   'the creation of an Mac application')
+
+  subparsers = parser.add_subparsers()
+
+  # Plist Parser
+
+  plist_parser = subparsers.add_parser('plist',
+                                       help='Process the Info.plist')
+  plist_parser.set_defaults(func=ProcessInfoPlist)
+  
+  plist_parser.add_argument('-i', dest='input', help='The input plist path')
+  plist_parser.add_argument('-o', dest='output', help='The output plist dir')
+
+  # NIB Parser
+
+  plist_parser = subparsers.add_parser('nib',
+                                       help='Process a NIB file')
+  plist_parser.set_defaults(func=ProcessNIB)
+  
+  plist_parser.add_argument('-i', dest='input', help='The input nib path')
+  plist_parser.add_argument('-o', dest='output', help='The output nib dir')
+  plist_parser.add_argument('-m', dest='module', help='The module name')
+
+  # Directory Structure Parser
+
+  dir_struct_parser = subparsers.add_parser('structure',
+                      help='Creates the directory of an Mac application')
+
+  dir_struct_parser.set_defaults(func=GenerateProjectStructure)
+
+  dir_struct_parser.add_argument('-d', dest='dir', help='Out directory')
+  dir_struct_parser.add_argument('-n', dest='name', help='App name')
+
+  # Engage!
+
+  args = parser.parse_args()
+
+  return args.func(args)
+
+
+if __name__ == '__main__':
+  sys.exit(Main())
diff --git a/build/config/mac/rules.gni b/build/config/mac/rules.gni
new file mode 100644
index 0000000000000000000000000000000000000000..8624beebe230dfaa9566fbd5ca1e63f378dcbea4
--- /dev/null
+++ b/build/config/mac/rules.gni
@@ -0,0 +1,216 @@
+# Copyright 2015 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.
+
+mac_app_script = "//build/config/mac/mac_app.py"
+
+template("code_sign_mac") {
+  assert(defined(invoker.entitlements_path),
+         "The path to the entitlements .xcent file")
+  assert(defined(invoker.identity),
+         "The code signing identity")
+  assert(defined(invoker.application_path),
+         "The application to code sign")
+  assert(defined(invoker.deps))
+
+  action(target_name) {
+    sources = [
+      invoker.entitlements_path,
+    ]
+
+    _application_path = invoker.application_path
+
+    script = mac_app_script
+
+    outputs = [
+      "$_application_path/_CodeSignature/CodeResources"
+    ]
+
+    args = [
+      "codesign",
+      "-p",
+      rebase_path(invoker.application_path, root_build_dir),
+      "-i",
+      invoker.identity,
+      "-e",
+      rebase_path(invoker.entitlements_path, root_build_dir),
+    ]
+
+    deps = invoker.deps
+  }
+}
+
+template("process_nibs_mac") {
+  assert(defined(invoker.sources),
+         "The nib sources must be specified")
+  assert(defined(invoker.module),
+         "The nib module must be specified")
+  assert(defined(invoker.output_dir),
+         "The output directory must be specified")
+
+  action_foreach(target_name) {
+    sources = invoker.sources
+
+    script = mac_app_script
+
+    invoker_out_dir = invoker.output_dir
+
+    outputs = [
+      "$root_build_dir/$invoker_out_dir/{{source_name_part}}.nib"
+    ]
+
+    args = [
+      "nib",
+      "-i",
+      "{{source}}",
+      "-o",
+      invoker_out_dir,
+      "-m",
+      invoker.module,
+    ]
+  }
+}
+
+template("resource_copy_mac") {
+  assert(defined(invoker.resources),
+         "The source list of resources to copy over")
+  assert(defined(invoker.bundle_directory),
+         "The directory within the bundle to place the sources in")
+  assert(defined(invoker.app_name),
+         "The name of the application")
+
+  _bundle_directory = invoker.bundle_directory
+  _app_name = invoker.app_name
+  _resources = invoker.resources
+
+  copy(target_name) {
+    set_sources_assignment_filter([])
+    sources = _resources
+    outputs = [ "$root_build_dir/$_app_name.app/$_bundle_directory/Contents/Resources/{{source_file_part}}" ]
+  }
+}
+
+template("mac_app") {
+
+  assert(defined(invoker.deps),
+         "Dependencies must be specified for $target_name")
+  assert(defined(invoker.info_plist),
+         "The application plist file must be specified for $target_name")
+  assert(defined(invoker.app_name),
+         "The name of Mac application for $target_name")
+  assert(defined(invoker.xibs),
+         "The list of XIB files must be specified for $target_name")
+  # assert(defined(invoker.entitlements_path),
+  #        "The entitlements path must be specified for $target_name")
+  # assert(defined(invoker.code_signing_identity),
+  #        "The entitlements path must be specified for $target_name")
+
+  # We just create a variable so we can use the same in interpolation
+  app_name = invoker.app_name
+
+  # Generate the project structure
+
+  struct_gen_target_name = target_name + "_struct"
+
+  action(struct_gen_target_name) {
+
+    script = mac_app_script
+
+    sources = []
+    outputs = [ "$root_build_dir/$app_name.app" ]
+
+    args = [
+      "structure",
+      "-d",
+      rebase_path(root_build_dir),
+      "-n",
+      app_name
+    ]
+
+  }
+
+  # Generate the executable
+
+  bin_gen_target_name = target_name + "_bin"
+
+  executable(bin_gen_target_name) {
+    deps = invoker.deps
+    output_name = app_name
+  }
+
+  # Process the Info.plist
+
+  plist_gen_target_name = target_name + "_plist"
+
+  action(plist_gen_target_name) {
+
+    script = mac_app_script
+
+    sources = [ invoker.info_plist ]
+    outputs = [ "$root_build_dir/Info.plist" ]
+
+    args = [
+      "plist",
+      "-i",
+      rebase_path(invoker.info_plist, root_build_dir),
+      "-o",
+      rebase_path(root_build_dir),
+    ]
+  }
+
+  # Copy the generated binaries and assets to their appropriate locations
+
+  copy_plist_gen_target_name = target_name + "_plist_copy"
+  copy(copy_plist_gen_target_name) {
+    sources = [
+      "$root_build_dir/Info.plist",
+    ]
+
+    outputs = [
+      "$root_build_dir/$app_name.app/Contents/{{source_file_part}}"
+    ]
+
+    deps = [
+      ":$plist_gen_target_name",
+    ]
+  }
+
+  copy_bin_target_name = target_name + "_bin_copy"
+  copy(copy_bin_target_name) {
+    sources = [
+      "$root_build_dir/$app_name",
+    ]
+
+    outputs = [
+      "$root_build_dir/$app_name.app/Contents/MacOS/{{source_file_part}}"
+    ]
+
+    deps = [
+      ":$bin_gen_target_name",
+    ]
+  }
+
+  copy_xib_target_name = target_name + "_xib_copy"
+  process_nibs_mac(copy_xib_target_name) {
+    sources = invoker.xibs
+    module = app_name
+    output_dir = "$app_name.app/Contents/Resources"
+  }
+
+  copy_all_target_name = target_name + "_all_copy"
+  group(copy_all_target_name) {
+    deps = [
+      ":$struct_gen_target_name",
+      ":$copy_plist_gen_target_name",
+      ":$copy_bin_target_name",
+      ":$copy_xib_target_name",
+    ]
+  }
+
+  # Top level group
+
+  group(target_name) {
+    deps = [ ":$copy_all_target_name" ]
+  }
+
+}
diff --git a/build/toolchain/mac/BUILD.gn b/build/toolchain/mac/BUILD.gn
index d16bb23b72a918d302fd7e7b5a12f6c2715cc24e..1b0277ad43bdc4a0c90b93f3958776228a3c50ee 100644
--- a/build/toolchain/mac/BUILD.gn
+++ b/build/toolchain/mac/BUILD.gn
@@ -7,11 +7,13 @@
 # Linux.
 
 import("../goma.gni")
+import("//build/config/ios/ios_sdk.gni")
 
 assert(host_os == "mac")
 
 import("//build/toolchain/clang.gni")
 import("//build/toolchain/goma.gni")
+import("//build/config/sysroot.gni")
 
 if (use_goma) {
   goma_prefix = "$goma_dir/gomacc "
@@ -36,6 +38,8 @@ template("mac_toolchain") {
            "mac_toolchain() must specify a \"toolchain_cpu\"")
     assert(defined(invoker.toolchain_os),
            "mac_toolchain() must specify a \"toolchain_os\"")
+    assert(defined(invoker.switch_sysroot),
+           "mac_toolchain() must specify a \"switch_sysroot\"")
 
     # We can't do string interpolation ($ in strings) on things with dots in
     # them. To allow us to use $cc below, for example, we create copies of
@@ -48,9 +52,23 @@ template("mac_toolchain") {
     lib_switch = "-l"
     lib_dir_switch = "-L"
 
+    sysroot_flags = ""
+
+    if (invoker.switch_sysroot) {
+      version_flags = ""
+
+      if (use_ios_simulator) {
+        version_flags = "-mios-simulator-version-min=$ios_deployment_target"
+      } else {
+        version_flags = "-miphoneos-version-min=$ios_deployment_target"
+      }
+
+      sysroot_flags = "-isysroot $sysroot $version_flags"
+    }
+
     tool("cc") {
       depfile = "{{output}}.d"
-      command = "$cc -MMD -MF $depfile {{defines}} {{include_dirs}} {{cflags}} {{cflags_c}} -c {{source}} -o {{output}}"
+      command = "$cc -MMD -MF $depfile {{defines}} {{include_dirs}} $sysroot_flags {{cflags}} {{cflags_c}} -c {{source}} -o {{output}}"
       depsformat = "gcc"
       description = "CC {{output}}"
       outputs = [
@@ -60,7 +78,7 @@ template("mac_toolchain") {
 
     tool("cxx") {
       depfile = "{{output}}.d"
-      command = "$cxx -MMD -MF $depfile {{defines}} {{include_dirs}} {{cflags}} {{cflags_cc}} -c {{source}} -o {{output}}"
+      command = "$cxx -MMD -MF $depfile {{defines}} {{include_dirs}} $sysroot_flags {{cflags}} {{cflags_cc}} -c {{source}} -o {{output}}"
       depsformat = "gcc"
       description = "CXX {{output}}"
       outputs = [
@@ -71,7 +89,7 @@ template("mac_toolchain") {
     tool("asm") {
       # For GCC we can just use the C compiler to compile assembly.
       depfile = "{{output}}.d"
-      command = "$cc -MMD -MF $depfile {{defines}} {{include_dirs}} {{cflags}} {{cflags_c}} -c {{source}} -o {{output}}"
+      command = "$cc -MMD -MF $depfile {{defines}} {{include_dirs}} $sysroot_flags {{cflags}} {{cflags_c}} -c {{source}} -o {{output}}"
       depsformat = "gcc"
       description = "ASM {{output}}"
       outputs = [
@@ -81,7 +99,7 @@ template("mac_toolchain") {
 
     tool("objc") {
       depfile = "{{output}}.d"
-      command = "$cxx -MMD -MF $depfile {{defines}} {{include_dirs}} {{cflags}} {{cflags_c}} {{cflags_objc}} -c {{source}} -o {{output}}"
+      command = "$cxx -MMD -MF $depfile {{defines}} {{include_dirs}} $sysroot_flags {{cflags}} {{cflags_c}} {{cflags_objc}} -c {{source}} -o {{output}}"
       depsformat = "gcc"
       description = "OBJC {{output}}"
       outputs = [
@@ -91,7 +109,7 @@ template("mac_toolchain") {
 
     tool("objcxx") {
       depfile = "{{output}}.d"
-      command = "$cxx -MMD -MF $depfile {{defines}} {{include_dirs}} {{cflags}} {{cflags_cc}} {{cflags_objcc}} -c {{source}} -o {{output}}"
+      command = "$cxx -MMD -MF $depfile {{defines}} {{include_dirs}} $sysroot_flags {{cflags}} {{cflags_cc}} {{cflags_objcc}} -c {{source}} -o {{output}}"
       depsformat = "gcc"
       description = "OBJCXX {{output}}"
       outputs = [
@@ -125,7 +143,7 @@ template("mac_toolchain") {
       temporary_tocname = dylib + ".tmp"
 
       does_reexport_command = "[ ! -e $dylib -o ! -e $tocname ] || otool -l $dylib | grep -q LC_REEXPORT_DYLIB"
-      link_command = "$ld -shared {{ldflags}} -o $dylib -Wl,-filelist,$rspfile {{solibs}} {{libs}}"
+      link_command = "$ld -shared $sysroot_flags {{ldflags}} -o $dylib -Wl,-filelist,$rspfile {{solibs}} {{libs}}"
       replace_command = "if ! cmp -s $temporary_tocname $tocname; then mv $temporary_tocname $tocname"
       extract_toc_command = "{ otool -l $dylib | grep LC_ID_DYLIB -A 5; nm -gP $dylib | cut -f1-2 -d' ' | grep -v U\$\$; true; }"
 
@@ -160,7 +178,7 @@ template("mac_toolchain") {
     tool("link") {
       outfile = "{{root_out_dir}}/{{target_output_name}}{{output_extension}}"
       rspfile = "$outfile.rsp"
-      command = "$ld {{ldflags}} -o $outfile -Wl,-filelist,$rspfile {{solibs}} {{libs}}"
+      command = "$ld $sysroot_flags {{ldflags}} -o $outfile -Wl,-filelist,$rspfile {{solibs}} {{libs}}"
       description = "LINK $outfile"
       rspfile_content = "{{inputs_newline}}"
       outputs = [
@@ -202,6 +220,19 @@ mac_toolchain("clang_arm") {
   cxx = "${goma_prefix}$prefix/clang++"
   ld = cxx
   is_clang = true
+  switch_sysroot = false
+}
+
+mac_toolchain("ios_clang_arm") {
+  toolchain_cpu = "arm"
+  toolchain_os = "mac"
+  prefix = rebase_path("//third_party/llvm-build/Release+Asserts/bin",
+                       root_build_dir)
+  cc = "${goma_prefix}$prefix/clang"
+  cxx = "${goma_prefix}$prefix/clang++"
+  ld = cxx
+  is_clang = true
+  switch_sysroot = true
 }
 
 mac_toolchain("arm") {
@@ -211,6 +242,7 @@ mac_toolchain("arm") {
   cxx = "${goma_prefix}/g++"
   ld = cxx
   is_clang = false
+  switch_sysroot = false
 }
 
 mac_toolchain("clang_x64") {
@@ -222,6 +254,7 @@ mac_toolchain("clang_x64") {
   cxx = "${goma_prefix}$prefix/clang++"
   ld = cxx
   is_clang = true
+  switch_sysroot = false
 }
 
 mac_toolchain("x64") {
@@ -231,4 +264,5 @@ mac_toolchain("x64") {
   cxx = "${goma_prefix}/g++"
   ld = cxx
   is_clang = false
+  switch_sysroot = false
 }