diff --git a/infra/recipes/gn.expected/ci_linux.json b/infra/recipes/gn.expected/ci_linux.json
new file mode 100644
index 0000000..45e521b
--- /dev/null
+++ b/infra/recipes/gn.expected/ci_linux.json
@@ -0,0 +1,217 @@
+[
+  {
+    "cmd": [],
+    "name": "git"
+  },
+  {
+    "cmd": [
+      "git",
+      "init",
+      "[START_DIR]/gn"
+    ],
+    "infra_step": true,
+    "name": "git.init",
+    "~followup_annotations": [
+      "@@@STEP_NEST_LEVEL@1@@@"
+    ]
+  },
+  {
+    "cmd": [
+      "git",
+      "fetch",
+      "--tags",
+      "https://gn.googlesource.com/gn",
+      "aaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaa"
+    ],
+    "cwd": "[START_DIR]/gn",
+    "infra_step": true,
+    "name": "git.fetch",
+    "~followup_annotations": [
+      "@@@STEP_NEST_LEVEL@1@@@"
+    ]
+  },
+  {
+    "cmd": [
+      "git",
+      "checkout",
+      "FETCH_HEAD"
+    ],
+    "cwd": "[START_DIR]/gn",
+    "infra_step": true,
+    "name": "git.checkout",
+    "~followup_annotations": [
+      "@@@STEP_NEST_LEVEL@1@@@"
+    ]
+  },
+  {
+    "cmd": [
+      "cipd",
+      "ensure",
+      "-root",
+      "[START_DIR]/cipd",
+      "-ensure-file",
+      "infra/ninja/${platform} version:1.8.2\nfuchsia/clang/${platform} goma",
+      "-json-output",
+      "/path/to/tmp/json"
+    ],
+    "infra_step": true,
+    "name": "ensure_installed",
+    "~followup_annotations": [
+      "@@@STEP_LOG_LINE@json.output@{@@@",
+      "@@@STEP_LOG_LINE@json.output@  \"result\": {@@@",
+      "@@@STEP_LOG_LINE@json.output@    \"\": [@@@",
+      "@@@STEP_LOG_LINE@json.output@      {@@@",
+      "@@@STEP_LOG_LINE@json.output@        \"instance_id\": \"resolved-instance_id-of-goma------------\", @@@",
+      "@@@STEP_LOG_LINE@json.output@        \"package\": \"fuchsia/clang/${platform}\"@@@",
+      "@@@STEP_LOG_LINE@json.output@      }, @@@",
+      "@@@STEP_LOG_LINE@json.output@      {@@@",
+      "@@@STEP_LOG_LINE@json.output@        \"instance_id\": \"resolved-instance_id-of-version:1.8.2---\", @@@",
+      "@@@STEP_LOG_LINE@json.output@        \"package\": \"infra/ninja/${platform}\"@@@",
+      "@@@STEP_LOG_LINE@json.output@      }@@@",
+      "@@@STEP_LOG_LINE@json.output@    ]@@@",
+      "@@@STEP_LOG_LINE@json.output@  }@@@",
+      "@@@STEP_LOG_LINE@json.output@}@@@",
+      "@@@STEP_LOG_END@json.output@@@"
+    ]
+  },
+  {
+    "cmd": [],
+    "name": "debug"
+  },
+  {
+    "cmd": [],
+    "name": "debug.build",
+    "~followup_annotations": [
+      "@@@STEP_NEST_LEVEL@1@@@"
+    ]
+  },
+  {
+    "cmd": [
+      "python",
+      "-u",
+      "[START_DIR]/gn/build/gen.py",
+      "-d"
+    ],
+    "cwd": "[START_DIR]/gn",
+    "env": {
+      "AR": "[START_DIR]/cipd/bin/llvm-ar",
+      "CC": "[START_DIR]/cipd/bin/clang",
+      "CXX": "[START_DIR]/cipd/bin/clang++",
+      "LDFLAGS": "-static-libstdc++ -ldl -lpthread"
+    },
+    "name": "debug.build.generate",
+    "~followup_annotations": [
+      "@@@STEP_NEST_LEVEL@2@@@"
+    ]
+  },
+  {
+    "cmd": [
+      "[START_DIR]/cipd/ninja",
+      "-C",
+      "[START_DIR]/gn/out"
+    ],
+    "cwd": "[START_DIR]/gn",
+    "env": {
+      "AR": "[START_DIR]/cipd/bin/llvm-ar",
+      "CC": "[START_DIR]/cipd/bin/clang",
+      "CXX": "[START_DIR]/cipd/bin/clang++",
+      "LDFLAGS": "-static-libstdc++ -ldl -lpthread"
+    },
+    "name": "debug.build.ninja",
+    "~followup_annotations": [
+      "@@@STEP_NEST_LEVEL@2@@@"
+    ]
+  },
+  {
+    "cmd": [
+      "[START_DIR]/gn/out/gn_unittests"
+    ],
+    "name": "debug.test",
+    "~followup_annotations": [
+      "@@@STEP_NEST_LEVEL@1@@@"
+    ]
+  },
+  {
+    "cmd": [],
+    "name": "release"
+  },
+  {
+    "cmd": [],
+    "name": "release.build",
+    "~followup_annotations": [
+      "@@@STEP_NEST_LEVEL@1@@@"
+    ]
+  },
+  {
+    "cmd": [
+      "python",
+      "-u",
+      "[START_DIR]/gn/build/gen.py"
+    ],
+    "cwd": "[START_DIR]/gn",
+    "env": {
+      "AR": "[START_DIR]/cipd/bin/llvm-ar",
+      "CC": "[START_DIR]/cipd/bin/clang",
+      "CXX": "[START_DIR]/cipd/bin/clang++",
+      "LDFLAGS": "-static-libstdc++ -ldl -lpthread"
+    },
+    "name": "release.build.generate",
+    "~followup_annotations": [
+      "@@@STEP_NEST_LEVEL@2@@@"
+    ]
+  },
+  {
+    "cmd": [
+      "[START_DIR]/cipd/ninja",
+      "-C",
+      "[START_DIR]/gn/out"
+    ],
+    "cwd": "[START_DIR]/gn",
+    "env": {
+      "AR": "[START_DIR]/cipd/bin/llvm-ar",
+      "CC": "[START_DIR]/cipd/bin/clang",
+      "CXX": "[START_DIR]/cipd/bin/clang++",
+      "LDFLAGS": "-static-libstdc++ -ldl -lpthread"
+    },
+    "name": "release.build.ninja",
+    "~followup_annotations": [
+      "@@@STEP_NEST_LEVEL@2@@@"
+    ]
+  },
+  {
+    "cmd": [
+      "[START_DIR]/gn/out/gn_unittests"
+    ],
+    "name": "release.test",
+    "~followup_annotations": [
+      "@@@STEP_NEST_LEVEL@1@@@"
+    ]
+  },
+  {
+    "cmd": [
+      "cipd",
+      "pkg-build",
+      "-pkg-def",
+      "{\"data\": [{\"file\": \"gn\"}, {\"version_file\": \".versions/gn.cipd_version\"}], \"install_mode\": \"copy\", \"package\": \"gn/gn/linux-amd64\", \"root\": \"[START_DIR]/gn/out\"}",
+      "-out",
+      "[CLEANUP]/gn.cipd",
+      "-json-output",
+      "/path/to/tmp/json"
+    ],
+    "name": "build gn/gn/linux-amd64",
+    "~followup_annotations": [
+      "@@@STEP_LOG_LINE@json.output@{@@@",
+      "@@@STEP_LOG_LINE@json.output@  \"result\": {@@@",
+      "@@@STEP_LOG_LINE@json.output@    \"instance_id\": \"40-chars-fake-of-the-package-instance_id\", @@@",
+      "@@@STEP_LOG_LINE@json.output@    \"package\": \"gn/gn/linux-amd64\"@@@",
+      "@@@STEP_LOG_LINE@json.output@  }@@@",
+      "@@@STEP_LOG_LINE@json.output@}@@@",
+      "@@@STEP_LOG_END@json.output@@@"
+    ]
+  },
+  {
+    "name": "$result",
+    "recipe_result": null,
+    "status_code": 0
+  }
+]
\ No newline at end of file
diff --git a/infra/recipes/gn.expected/ci_mac.json b/infra/recipes/gn.expected/ci_mac.json
new file mode 100644
index 0000000..fbd3119
--- /dev/null
+++ b/infra/recipes/gn.expected/ci_mac.json
@@ -0,0 +1,337 @@
+[
+  {
+    "cmd": [],
+    "name": "git"
+  },
+  {
+    "cmd": [
+      "git",
+      "init",
+      "[START_DIR]/gn"
+    ],
+    "infra_step": true,
+    "name": "git.init",
+    "~followup_annotations": [
+      "@@@STEP_NEST_LEVEL@1@@@"
+    ]
+  },
+  {
+    "cmd": [
+      "git",
+      "fetch",
+      "--tags",
+      "https://gn.googlesource.com/gn",
+      "aaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaa"
+    ],
+    "cwd": "[START_DIR]/gn",
+    "infra_step": true,
+    "name": "git.fetch",
+    "~followup_annotations": [
+      "@@@STEP_NEST_LEVEL@1@@@"
+    ]
+  },
+  {
+    "cmd": [
+      "git",
+      "checkout",
+      "FETCH_HEAD"
+    ],
+    "cwd": "[START_DIR]/gn",
+    "infra_step": true,
+    "name": "git.checkout",
+    "~followup_annotations": [
+      "@@@STEP_NEST_LEVEL@1@@@"
+    ]
+  },
+  {
+    "cmd": [
+      "cipd",
+      "ensure",
+      "-root",
+      "[START_DIR]/cipd",
+      "-ensure-file",
+      "infra/ninja/${platform} version:1.8.2",
+      "-json-output",
+      "/path/to/tmp/json"
+    ],
+    "infra_step": true,
+    "name": "ensure_installed",
+    "~followup_annotations": [
+      "@@@STEP_LOG_LINE@json.output@{@@@",
+      "@@@STEP_LOG_LINE@json.output@  \"result\": {@@@",
+      "@@@STEP_LOG_LINE@json.output@    \"\": [@@@",
+      "@@@STEP_LOG_LINE@json.output@      {@@@",
+      "@@@STEP_LOG_LINE@json.output@        \"instance_id\": \"resolved-instance_id-of-version:1.8.2---\", @@@",
+      "@@@STEP_LOG_LINE@json.output@        \"package\": \"infra/ninja/${platform}\"@@@",
+      "@@@STEP_LOG_LINE@json.output@      }@@@",
+      "@@@STEP_LOG_LINE@json.output@    ]@@@",
+      "@@@STEP_LOG_LINE@json.output@  }@@@",
+      "@@@STEP_LOG_LINE@json.output@}@@@",
+      "@@@STEP_LOG_END@json.output@@@"
+    ]
+  },
+  {
+    "cmd": [],
+    "name": "debug"
+  },
+  {
+    "cmd": [],
+    "name": "debug.build",
+    "~followup_annotations": [
+      "@@@STEP_NEST_LEVEL@1@@@"
+    ]
+  },
+  {
+    "cmd": [
+      "cipd",
+      "ensure",
+      "-root",
+      "[CACHE]/macos_sdk",
+      "-ensure-file",
+      "infra/tools/mac_toolchain/${platform} git_revision:796d2b92cff93fc2059623ce0a66284373ceea0a",
+      "-json-output",
+      "/path/to/tmp/json"
+    ],
+    "cwd": "[START_DIR]/gn",
+    "infra_step": true,
+    "name": "debug.build.ensure_installed",
+    "~followup_annotations": [
+      "@@@STEP_NEST_LEVEL@2@@@",
+      "@@@STEP_LOG_LINE@json.output@{@@@",
+      "@@@STEP_LOG_LINE@json.output@  \"result\": {@@@",
+      "@@@STEP_LOG_LINE@json.output@    \"\": [@@@",
+      "@@@STEP_LOG_LINE@json.output@      {@@@",
+      "@@@STEP_LOG_LINE@json.output@        \"instance_id\": \"resolved-instance_id-of-git_revision:796\", @@@",
+      "@@@STEP_LOG_LINE@json.output@        \"package\": \"infra/tools/mac_toolchain/${platform}\"@@@",
+      "@@@STEP_LOG_LINE@json.output@      }@@@",
+      "@@@STEP_LOG_LINE@json.output@    ]@@@",
+      "@@@STEP_LOG_LINE@json.output@  }@@@",
+      "@@@STEP_LOG_LINE@json.output@}@@@",
+      "@@@STEP_LOG_END@json.output@@@"
+    ]
+  },
+  {
+    "cmd": [
+      "[CACHE]/macos_sdk/mac_toolchain",
+      "install",
+      "-kind",
+      "mac",
+      "-xcode-version",
+      "9c40b",
+      "-output-dir",
+      "[CACHE]/macos_sdk/XCode.app"
+    ],
+    "cwd": "[START_DIR]/gn",
+    "infra_step": true,
+    "name": "debug.build.install xcode",
+    "~followup_annotations": [
+      "@@@STEP_NEST_LEVEL@2@@@"
+    ]
+  },
+  {
+    "cmd": [
+      "sudo",
+      "xcode-select",
+      "--switch",
+      "[CACHE]/macos_sdk/XCode.app"
+    ],
+    "cwd": "[START_DIR]/gn",
+    "infra_step": true,
+    "name": "debug.build.select XCode",
+    "~followup_annotations": [
+      "@@@STEP_NEST_LEVEL@2@@@"
+    ]
+  },
+  {
+    "cmd": [
+      "python",
+      "-u",
+      "[START_DIR]/gn/build/gen.py",
+      "-d"
+    ],
+    "cwd": "[START_DIR]/gn",
+    "name": "debug.build.generate",
+    "~followup_annotations": [
+      "@@@STEP_NEST_LEVEL@2@@@"
+    ]
+  },
+  {
+    "cmd": [
+      "[START_DIR]/cipd/ninja",
+      "-C",
+      "[START_DIR]/gn/out"
+    ],
+    "cwd": "[START_DIR]/gn",
+    "name": "debug.build.ninja",
+    "~followup_annotations": [
+      "@@@STEP_NEST_LEVEL@2@@@"
+    ]
+  },
+  {
+    "cmd": [
+      "sudo",
+      "xcode-select",
+      "--reset"
+    ],
+    "cwd": "[START_DIR]/gn",
+    "infra_step": true,
+    "name": "debug.build.reset XCode",
+    "~followup_annotations": [
+      "@@@STEP_NEST_LEVEL@2@@@"
+    ]
+  },
+  {
+    "cmd": [
+      "[START_DIR]/gn/out/gn_unittests"
+    ],
+    "name": "debug.test",
+    "~followup_annotations": [
+      "@@@STEP_NEST_LEVEL@1@@@"
+    ]
+  },
+  {
+    "cmd": [],
+    "name": "release"
+  },
+  {
+    "cmd": [],
+    "name": "release.build",
+    "~followup_annotations": [
+      "@@@STEP_NEST_LEVEL@1@@@"
+    ]
+  },
+  {
+    "cmd": [
+      "cipd",
+      "ensure",
+      "-root",
+      "[CACHE]/macos_sdk",
+      "-ensure-file",
+      "infra/tools/mac_toolchain/${platform} git_revision:796d2b92cff93fc2059623ce0a66284373ceea0a",
+      "-json-output",
+      "/path/to/tmp/json"
+    ],
+    "cwd": "[START_DIR]/gn",
+    "infra_step": true,
+    "name": "release.build.ensure_installed",
+    "~followup_annotations": [
+      "@@@STEP_NEST_LEVEL@2@@@",
+      "@@@STEP_LOG_LINE@json.output@{@@@",
+      "@@@STEP_LOG_LINE@json.output@  \"result\": {@@@",
+      "@@@STEP_LOG_LINE@json.output@    \"\": [@@@",
+      "@@@STEP_LOG_LINE@json.output@      {@@@",
+      "@@@STEP_LOG_LINE@json.output@        \"instance_id\": \"resolved-instance_id-of-git_revision:796\", @@@",
+      "@@@STEP_LOG_LINE@json.output@        \"package\": \"infra/tools/mac_toolchain/${platform}\"@@@",
+      "@@@STEP_LOG_LINE@json.output@      }@@@",
+      "@@@STEP_LOG_LINE@json.output@    ]@@@",
+      "@@@STEP_LOG_LINE@json.output@  }@@@",
+      "@@@STEP_LOG_LINE@json.output@}@@@",
+      "@@@STEP_LOG_END@json.output@@@"
+    ]
+  },
+  {
+    "cmd": [
+      "[CACHE]/macos_sdk/mac_toolchain",
+      "install",
+      "-kind",
+      "mac",
+      "-xcode-version",
+      "9c40b",
+      "-output-dir",
+      "[CACHE]/macos_sdk/XCode.app"
+    ],
+    "cwd": "[START_DIR]/gn",
+    "infra_step": true,
+    "name": "release.build.install xcode",
+    "~followup_annotations": [
+      "@@@STEP_NEST_LEVEL@2@@@"
+    ]
+  },
+  {
+    "cmd": [
+      "sudo",
+      "xcode-select",
+      "--switch",
+      "[CACHE]/macos_sdk/XCode.app"
+    ],
+    "cwd": "[START_DIR]/gn",
+    "infra_step": true,
+    "name": "release.build.select XCode",
+    "~followup_annotations": [
+      "@@@STEP_NEST_LEVEL@2@@@"
+    ]
+  },
+  {
+    "cmd": [
+      "python",
+      "-u",
+      "[START_DIR]/gn/build/gen.py"
+    ],
+    "cwd": "[START_DIR]/gn",
+    "name": "release.build.generate",
+    "~followup_annotations": [
+      "@@@STEP_NEST_LEVEL@2@@@"
+    ]
+  },
+  {
+    "cmd": [
+      "[START_DIR]/cipd/ninja",
+      "-C",
+      "[START_DIR]/gn/out"
+    ],
+    "cwd": "[START_DIR]/gn",
+    "name": "release.build.ninja",
+    "~followup_annotations": [
+      "@@@STEP_NEST_LEVEL@2@@@"
+    ]
+  },
+  {
+    "cmd": [
+      "sudo",
+      "xcode-select",
+      "--reset"
+    ],
+    "cwd": "[START_DIR]/gn",
+    "infra_step": true,
+    "name": "release.build.reset XCode",
+    "~followup_annotations": [
+      "@@@STEP_NEST_LEVEL@2@@@"
+    ]
+  },
+  {
+    "cmd": [
+      "[START_DIR]/gn/out/gn_unittests"
+    ],
+    "name": "release.test",
+    "~followup_annotations": [
+      "@@@STEP_NEST_LEVEL@1@@@"
+    ]
+  },
+  {
+    "cmd": [
+      "cipd",
+      "pkg-build",
+      "-pkg-def",
+      "{\"data\": [{\"file\": \"gn\"}, {\"version_file\": \".versions/gn.cipd_version\"}], \"install_mode\": \"copy\", \"package\": \"gn/gn/mac-amd64\", \"root\": \"[START_DIR]/gn/out\"}",
+      "-out",
+      "[CLEANUP]/gn.cipd",
+      "-json-output",
+      "/path/to/tmp/json"
+    ],
+    "name": "build gn/gn/mac-amd64",
+    "~followup_annotations": [
+      "@@@STEP_LOG_LINE@json.output@{@@@",
+      "@@@STEP_LOG_LINE@json.output@  \"result\": {@@@",
+      "@@@STEP_LOG_LINE@json.output@    \"instance_id\": \"40-chars-fake-of-the-package-instance_id\", @@@",
+      "@@@STEP_LOG_LINE@json.output@    \"package\": \"gn/gn/mac-amd64\"@@@",
+      "@@@STEP_LOG_LINE@json.output@  }@@@",
+      "@@@STEP_LOG_LINE@json.output@}@@@",
+      "@@@STEP_LOG_END@json.output@@@"
+    ]
+  },
+  {
+    "name": "$result",
+    "recipe_result": null,
+    "status_code": 0
+  }
+]
\ No newline at end of file
diff --git a/infra/recipes/gn.expected/ci.json b/infra/recipes/gn.expected/ci_win.json
similarity index 93%
rename from infra/recipes/gn.expected/ci.json
rename to infra/recipes/gn.expected/ci_win.json
index e2e8933..dacb8eb 100644
--- a/infra/recipes/gn.expected/ci.json
+++ b/infra/recipes/gn.expected/ci_win.json
@@ -86,7 +86,7 @@
       "cipd.bat",
       "ensure",
       "-root",
-      "[START_DIR]\\cipd\\windows_sdk",
+      "[CACHE]\\windows_sdk",
       "-ensure-file",
       "chrome_internal/third_party/sdk/windows uploaded:2018-06-13",
       "-json-output",
@@ -115,7 +115,7 @@
       "python",
       "-u",
       "\nimport shutil\nimport sys\nshutil.copy(sys.argv[1], sys.argv[2])\n",
-      "[START_DIR]\\cipd\\windows_sdk\\win_sdk\\bin\\SetEnv.x64.json",
+      "[CACHE]\\windows_sdk\\win_sdk\\bin\\SetEnv.x64.json",
       "/path/to/tmp/json"
     ],
     "cwd": "[START_DIR]\\gn",
@@ -153,11 +153,11 @@
     ],
     "cwd": "[START_DIR]\\gn",
     "env": {
-      "VSINSTALLDIR": "[START_DIR]\\cipd\\windows_sdk"
+      "VSINSTALLDIR": "[CACHE]\\windows_sdk"
     },
     "env_prefixes": {
       "PATH": [
-        "[START_DIR]\\cipd\\windows_sdk\\win_sdk\\bin\\x64"
+        "[CACHE]\\windows_sdk\\win_sdk\\bin\\x64"
       ]
     },
     "name": "debug.build.generate",
@@ -173,11 +173,11 @@
     ],
     "cwd": "[START_DIR]\\gn",
     "env": {
-      "VSINSTALLDIR": "[START_DIR]\\cipd\\windows_sdk"
+      "VSINSTALLDIR": "[CACHE]\\windows_sdk"
     },
     "env_prefixes": {
       "PATH": [
-        "[START_DIR]\\cipd\\windows_sdk\\win_sdk\\bin\\x64"
+        "[CACHE]\\windows_sdk\\win_sdk\\bin\\x64"
       ]
     },
     "name": "debug.build.ninja",
@@ -224,7 +224,7 @@
       "cipd.bat",
       "ensure",
       "-root",
-      "[START_DIR]\\cipd\\windows_sdk",
+      "[CACHE]\\windows_sdk",
       "-ensure-file",
       "chrome_internal/third_party/sdk/windows uploaded:2018-06-13",
       "-json-output",
@@ -253,7 +253,7 @@
       "python",
       "-u",
       "\nimport shutil\nimport sys\nshutil.copy(sys.argv[1], sys.argv[2])\n",
-      "[START_DIR]\\cipd\\windows_sdk\\win_sdk\\bin\\SetEnv.x64.json",
+      "[CACHE]\\windows_sdk\\win_sdk\\bin\\SetEnv.x64.json",
       "/path/to/tmp/json"
     ],
     "cwd": "[START_DIR]\\gn",
@@ -290,11 +290,11 @@
     ],
     "cwd": "[START_DIR]\\gn",
     "env": {
-      "VSINSTALLDIR": "[START_DIR]\\cipd\\windows_sdk"
+      "VSINSTALLDIR": "[CACHE]\\windows_sdk"
     },
     "env_prefixes": {
       "PATH": [
-        "[START_DIR]\\cipd\\windows_sdk\\win_sdk\\bin\\x64"
+        "[CACHE]\\windows_sdk\\win_sdk\\bin\\x64"
       ]
     },
     "name": "release.build.generate",
@@ -310,11 +310,11 @@
     ],
     "cwd": "[START_DIR]\\gn",
     "env": {
-      "VSINSTALLDIR": "[START_DIR]\\cipd\\windows_sdk"
+      "VSINSTALLDIR": "[CACHE]\\windows_sdk"
     },
     "env_prefixes": {
       "PATH": [
-        "[START_DIR]\\cipd\\windows_sdk\\win_sdk\\bin\\x64"
+        "[CACHE]\\windows_sdk\\win_sdk\\bin\\x64"
       ]
     },
     "name": "release.build.ninja",
diff --git a/infra/recipes/gn.expected/cq_linux.json b/infra/recipes/gn.expected/cq_linux.json
new file mode 100644
index 0000000..f7309c0
--- /dev/null
+++ b/infra/recipes/gn.expected/cq_linux.json
@@ -0,0 +1,222 @@
+[
+  {
+    "cmd": [],
+    "name": "git"
+  },
+  {
+    "cmd": [
+      "git",
+      "init",
+      "[START_DIR]/gn"
+    ],
+    "infra_step": true,
+    "name": "git.init",
+    "~followup_annotations": [
+      "@@@STEP_NEST_LEVEL@1@@@"
+    ]
+  },
+  {
+    "cmd": [
+      "git",
+      "fetch",
+      "--tags",
+      "https://gn.googlesource.com/gn",
+      "refs/heads/master"
+    ],
+    "cwd": "[START_DIR]/gn",
+    "infra_step": true,
+    "name": "git.fetch",
+    "~followup_annotations": [
+      "@@@STEP_NEST_LEVEL@1@@@"
+    ]
+  },
+  {
+    "cmd": [
+      "git",
+      "checkout",
+      "FETCH_HEAD"
+    ],
+    "cwd": "[START_DIR]/gn",
+    "infra_step": true,
+    "name": "git.checkout",
+    "~followup_annotations": [
+      "@@@STEP_NEST_LEVEL@1@@@"
+    ]
+  },
+  {
+    "cmd": [
+      "git",
+      "fetch",
+      "https://gn.googlesource.com/gn",
+      "refs/changes/00/1000/1"
+    ],
+    "cwd": "[START_DIR]/gn",
+    "infra_step": true,
+    "name": "git.fetch 1000/1",
+    "~followup_annotations": [
+      "@@@STEP_NEST_LEVEL@1@@@"
+    ]
+  },
+  {
+    "cmd": [
+      "git",
+      "cherry-pick",
+      "FETCH_HEAD"
+    ],
+    "cwd": "[START_DIR]/gn",
+    "infra_step": true,
+    "name": "git.cherry-pick 1000/1",
+    "~followup_annotations": [
+      "@@@STEP_NEST_LEVEL@1@@@"
+    ]
+  },
+  {
+    "cmd": [
+      "cipd",
+      "ensure",
+      "-root",
+      "[START_DIR]/cipd",
+      "-ensure-file",
+      "infra/ninja/${platform} version:1.8.2\nfuchsia/clang/${platform} goma",
+      "-json-output",
+      "/path/to/tmp/json"
+    ],
+    "infra_step": true,
+    "name": "ensure_installed",
+    "~followup_annotations": [
+      "@@@STEP_LOG_LINE@json.output@{@@@",
+      "@@@STEP_LOG_LINE@json.output@  \"result\": {@@@",
+      "@@@STEP_LOG_LINE@json.output@    \"\": [@@@",
+      "@@@STEP_LOG_LINE@json.output@      {@@@",
+      "@@@STEP_LOG_LINE@json.output@        \"instance_id\": \"resolved-instance_id-of-goma------------\", @@@",
+      "@@@STEP_LOG_LINE@json.output@        \"package\": \"fuchsia/clang/${platform}\"@@@",
+      "@@@STEP_LOG_LINE@json.output@      }, @@@",
+      "@@@STEP_LOG_LINE@json.output@      {@@@",
+      "@@@STEP_LOG_LINE@json.output@        \"instance_id\": \"resolved-instance_id-of-version:1.8.2---\", @@@",
+      "@@@STEP_LOG_LINE@json.output@        \"package\": \"infra/ninja/${platform}\"@@@",
+      "@@@STEP_LOG_LINE@json.output@      }@@@",
+      "@@@STEP_LOG_LINE@json.output@    ]@@@",
+      "@@@STEP_LOG_LINE@json.output@  }@@@",
+      "@@@STEP_LOG_LINE@json.output@}@@@",
+      "@@@STEP_LOG_END@json.output@@@"
+    ]
+  },
+  {
+    "cmd": [],
+    "name": "debug"
+  },
+  {
+    "cmd": [],
+    "name": "debug.build",
+    "~followup_annotations": [
+      "@@@STEP_NEST_LEVEL@1@@@"
+    ]
+  },
+  {
+    "cmd": [
+      "python",
+      "-u",
+      "[START_DIR]/gn/build/gen.py",
+      "-d"
+    ],
+    "cwd": "[START_DIR]/gn",
+    "env": {
+      "AR": "[START_DIR]/cipd/bin/llvm-ar",
+      "CC": "[START_DIR]/cipd/bin/clang",
+      "CXX": "[START_DIR]/cipd/bin/clang++",
+      "LDFLAGS": "-static-libstdc++ -ldl -lpthread"
+    },
+    "name": "debug.build.generate",
+    "~followup_annotations": [
+      "@@@STEP_NEST_LEVEL@2@@@"
+    ]
+  },
+  {
+    "cmd": [
+      "[START_DIR]/cipd/ninja",
+      "-C",
+      "[START_DIR]/gn/out"
+    ],
+    "cwd": "[START_DIR]/gn",
+    "env": {
+      "AR": "[START_DIR]/cipd/bin/llvm-ar",
+      "CC": "[START_DIR]/cipd/bin/clang",
+      "CXX": "[START_DIR]/cipd/bin/clang++",
+      "LDFLAGS": "-static-libstdc++ -ldl -lpthread"
+    },
+    "name": "debug.build.ninja",
+    "~followup_annotations": [
+      "@@@STEP_NEST_LEVEL@2@@@"
+    ]
+  },
+  {
+    "cmd": [
+      "[START_DIR]/gn/out/gn_unittests"
+    ],
+    "name": "debug.test",
+    "~followup_annotations": [
+      "@@@STEP_NEST_LEVEL@1@@@"
+    ]
+  },
+  {
+    "cmd": [],
+    "name": "release"
+  },
+  {
+    "cmd": [],
+    "name": "release.build",
+    "~followup_annotations": [
+      "@@@STEP_NEST_LEVEL@1@@@"
+    ]
+  },
+  {
+    "cmd": [
+      "python",
+      "-u",
+      "[START_DIR]/gn/build/gen.py"
+    ],
+    "cwd": "[START_DIR]/gn",
+    "env": {
+      "AR": "[START_DIR]/cipd/bin/llvm-ar",
+      "CC": "[START_DIR]/cipd/bin/clang",
+      "CXX": "[START_DIR]/cipd/bin/clang++",
+      "LDFLAGS": "-static-libstdc++ -ldl -lpthread"
+    },
+    "name": "release.build.generate",
+    "~followup_annotations": [
+      "@@@STEP_NEST_LEVEL@2@@@"
+    ]
+  },
+  {
+    "cmd": [
+      "[START_DIR]/cipd/ninja",
+      "-C",
+      "[START_DIR]/gn/out"
+    ],
+    "cwd": "[START_DIR]/gn",
+    "env": {
+      "AR": "[START_DIR]/cipd/bin/llvm-ar",
+      "CC": "[START_DIR]/cipd/bin/clang",
+      "CXX": "[START_DIR]/cipd/bin/clang++",
+      "LDFLAGS": "-static-libstdc++ -ldl -lpthread"
+    },
+    "name": "release.build.ninja",
+    "~followup_annotations": [
+      "@@@STEP_NEST_LEVEL@2@@@"
+    ]
+  },
+  {
+    "cmd": [
+      "[START_DIR]/gn/out/gn_unittests"
+    ],
+    "name": "release.test",
+    "~followup_annotations": [
+      "@@@STEP_NEST_LEVEL@1@@@"
+    ]
+  },
+  {
+    "name": "$result",
+    "recipe_result": null,
+    "status_code": 0
+  }
+]
\ No newline at end of file
diff --git a/infra/recipes/gn.expected/cq_mac.json b/infra/recipes/gn.expected/cq_mac.json
new file mode 100644
index 0000000..1b0e09c
--- /dev/null
+++ b/infra/recipes/gn.expected/cq_mac.json
@@ -0,0 +1,342 @@
+[
+  {
+    "cmd": [],
+    "name": "git"
+  },
+  {
+    "cmd": [
+      "git",
+      "init",
+      "[START_DIR]/gn"
+    ],
+    "infra_step": true,
+    "name": "git.init",
+    "~followup_annotations": [
+      "@@@STEP_NEST_LEVEL@1@@@"
+    ]
+  },
+  {
+    "cmd": [
+      "git",
+      "fetch",
+      "--tags",
+      "https://gn.googlesource.com/gn",
+      "refs/heads/master"
+    ],
+    "cwd": "[START_DIR]/gn",
+    "infra_step": true,
+    "name": "git.fetch",
+    "~followup_annotations": [
+      "@@@STEP_NEST_LEVEL@1@@@"
+    ]
+  },
+  {
+    "cmd": [
+      "git",
+      "checkout",
+      "FETCH_HEAD"
+    ],
+    "cwd": "[START_DIR]/gn",
+    "infra_step": true,
+    "name": "git.checkout",
+    "~followup_annotations": [
+      "@@@STEP_NEST_LEVEL@1@@@"
+    ]
+  },
+  {
+    "cmd": [
+      "git",
+      "fetch",
+      "https://gn.googlesource.com/gn",
+      "refs/changes/00/1000/1"
+    ],
+    "cwd": "[START_DIR]/gn",
+    "infra_step": true,
+    "name": "git.fetch 1000/1",
+    "~followup_annotations": [
+      "@@@STEP_NEST_LEVEL@1@@@"
+    ]
+  },
+  {
+    "cmd": [
+      "git",
+      "cherry-pick",
+      "FETCH_HEAD"
+    ],
+    "cwd": "[START_DIR]/gn",
+    "infra_step": true,
+    "name": "git.cherry-pick 1000/1",
+    "~followup_annotations": [
+      "@@@STEP_NEST_LEVEL@1@@@"
+    ]
+  },
+  {
+    "cmd": [
+      "cipd",
+      "ensure",
+      "-root",
+      "[START_DIR]/cipd",
+      "-ensure-file",
+      "infra/ninja/${platform} version:1.8.2",
+      "-json-output",
+      "/path/to/tmp/json"
+    ],
+    "infra_step": true,
+    "name": "ensure_installed",
+    "~followup_annotations": [
+      "@@@STEP_LOG_LINE@json.output@{@@@",
+      "@@@STEP_LOG_LINE@json.output@  \"result\": {@@@",
+      "@@@STEP_LOG_LINE@json.output@    \"\": [@@@",
+      "@@@STEP_LOG_LINE@json.output@      {@@@",
+      "@@@STEP_LOG_LINE@json.output@        \"instance_id\": \"resolved-instance_id-of-version:1.8.2---\", @@@",
+      "@@@STEP_LOG_LINE@json.output@        \"package\": \"infra/ninja/${platform}\"@@@",
+      "@@@STEP_LOG_LINE@json.output@      }@@@",
+      "@@@STEP_LOG_LINE@json.output@    ]@@@",
+      "@@@STEP_LOG_LINE@json.output@  }@@@",
+      "@@@STEP_LOG_LINE@json.output@}@@@",
+      "@@@STEP_LOG_END@json.output@@@"
+    ]
+  },
+  {
+    "cmd": [],
+    "name": "debug"
+  },
+  {
+    "cmd": [],
+    "name": "debug.build",
+    "~followup_annotations": [
+      "@@@STEP_NEST_LEVEL@1@@@"
+    ]
+  },
+  {
+    "cmd": [
+      "cipd",
+      "ensure",
+      "-root",
+      "[CACHE]/macos_sdk",
+      "-ensure-file",
+      "infra/tools/mac_toolchain/${platform} git_revision:796d2b92cff93fc2059623ce0a66284373ceea0a",
+      "-json-output",
+      "/path/to/tmp/json"
+    ],
+    "cwd": "[START_DIR]/gn",
+    "infra_step": true,
+    "name": "debug.build.ensure_installed",
+    "~followup_annotations": [
+      "@@@STEP_NEST_LEVEL@2@@@",
+      "@@@STEP_LOG_LINE@json.output@{@@@",
+      "@@@STEP_LOG_LINE@json.output@  \"result\": {@@@",
+      "@@@STEP_LOG_LINE@json.output@    \"\": [@@@",
+      "@@@STEP_LOG_LINE@json.output@      {@@@",
+      "@@@STEP_LOG_LINE@json.output@        \"instance_id\": \"resolved-instance_id-of-git_revision:796\", @@@",
+      "@@@STEP_LOG_LINE@json.output@        \"package\": \"infra/tools/mac_toolchain/${platform}\"@@@",
+      "@@@STEP_LOG_LINE@json.output@      }@@@",
+      "@@@STEP_LOG_LINE@json.output@    ]@@@",
+      "@@@STEP_LOG_LINE@json.output@  }@@@",
+      "@@@STEP_LOG_LINE@json.output@}@@@",
+      "@@@STEP_LOG_END@json.output@@@"
+    ]
+  },
+  {
+    "cmd": [
+      "[CACHE]/macos_sdk/mac_toolchain",
+      "install",
+      "-kind",
+      "mac",
+      "-xcode-version",
+      "9c40b",
+      "-output-dir",
+      "[CACHE]/macos_sdk/XCode.app"
+    ],
+    "cwd": "[START_DIR]/gn",
+    "infra_step": true,
+    "name": "debug.build.install xcode",
+    "~followup_annotations": [
+      "@@@STEP_NEST_LEVEL@2@@@"
+    ]
+  },
+  {
+    "cmd": [
+      "sudo",
+      "xcode-select",
+      "--switch",
+      "[CACHE]/macos_sdk/XCode.app"
+    ],
+    "cwd": "[START_DIR]/gn",
+    "infra_step": true,
+    "name": "debug.build.select XCode",
+    "~followup_annotations": [
+      "@@@STEP_NEST_LEVEL@2@@@"
+    ]
+  },
+  {
+    "cmd": [
+      "python",
+      "-u",
+      "[START_DIR]/gn/build/gen.py",
+      "-d"
+    ],
+    "cwd": "[START_DIR]/gn",
+    "name": "debug.build.generate",
+    "~followup_annotations": [
+      "@@@STEP_NEST_LEVEL@2@@@"
+    ]
+  },
+  {
+    "cmd": [
+      "[START_DIR]/cipd/ninja",
+      "-C",
+      "[START_DIR]/gn/out"
+    ],
+    "cwd": "[START_DIR]/gn",
+    "name": "debug.build.ninja",
+    "~followup_annotations": [
+      "@@@STEP_NEST_LEVEL@2@@@"
+    ]
+  },
+  {
+    "cmd": [
+      "sudo",
+      "xcode-select",
+      "--reset"
+    ],
+    "cwd": "[START_DIR]/gn",
+    "infra_step": true,
+    "name": "debug.build.reset XCode",
+    "~followup_annotations": [
+      "@@@STEP_NEST_LEVEL@2@@@"
+    ]
+  },
+  {
+    "cmd": [
+      "[START_DIR]/gn/out/gn_unittests"
+    ],
+    "name": "debug.test",
+    "~followup_annotations": [
+      "@@@STEP_NEST_LEVEL@1@@@"
+    ]
+  },
+  {
+    "cmd": [],
+    "name": "release"
+  },
+  {
+    "cmd": [],
+    "name": "release.build",
+    "~followup_annotations": [
+      "@@@STEP_NEST_LEVEL@1@@@"
+    ]
+  },
+  {
+    "cmd": [
+      "cipd",
+      "ensure",
+      "-root",
+      "[CACHE]/macos_sdk",
+      "-ensure-file",
+      "infra/tools/mac_toolchain/${platform} git_revision:796d2b92cff93fc2059623ce0a66284373ceea0a",
+      "-json-output",
+      "/path/to/tmp/json"
+    ],
+    "cwd": "[START_DIR]/gn",
+    "infra_step": true,
+    "name": "release.build.ensure_installed",
+    "~followup_annotations": [
+      "@@@STEP_NEST_LEVEL@2@@@",
+      "@@@STEP_LOG_LINE@json.output@{@@@",
+      "@@@STEP_LOG_LINE@json.output@  \"result\": {@@@",
+      "@@@STEP_LOG_LINE@json.output@    \"\": [@@@",
+      "@@@STEP_LOG_LINE@json.output@      {@@@",
+      "@@@STEP_LOG_LINE@json.output@        \"instance_id\": \"resolved-instance_id-of-git_revision:796\", @@@",
+      "@@@STEP_LOG_LINE@json.output@        \"package\": \"infra/tools/mac_toolchain/${platform}\"@@@",
+      "@@@STEP_LOG_LINE@json.output@      }@@@",
+      "@@@STEP_LOG_LINE@json.output@    ]@@@",
+      "@@@STEP_LOG_LINE@json.output@  }@@@",
+      "@@@STEP_LOG_LINE@json.output@}@@@",
+      "@@@STEP_LOG_END@json.output@@@"
+    ]
+  },
+  {
+    "cmd": [
+      "[CACHE]/macos_sdk/mac_toolchain",
+      "install",
+      "-kind",
+      "mac",
+      "-xcode-version",
+      "9c40b",
+      "-output-dir",
+      "[CACHE]/macos_sdk/XCode.app"
+    ],
+    "cwd": "[START_DIR]/gn",
+    "infra_step": true,
+    "name": "release.build.install xcode",
+    "~followup_annotations": [
+      "@@@STEP_NEST_LEVEL@2@@@"
+    ]
+  },
+  {
+    "cmd": [
+      "sudo",
+      "xcode-select",
+      "--switch",
+      "[CACHE]/macos_sdk/XCode.app"
+    ],
+    "cwd": "[START_DIR]/gn",
+    "infra_step": true,
+    "name": "release.build.select XCode",
+    "~followup_annotations": [
+      "@@@STEP_NEST_LEVEL@2@@@"
+    ]
+  },
+  {
+    "cmd": [
+      "python",
+      "-u",
+      "[START_DIR]/gn/build/gen.py"
+    ],
+    "cwd": "[START_DIR]/gn",
+    "name": "release.build.generate",
+    "~followup_annotations": [
+      "@@@STEP_NEST_LEVEL@2@@@"
+    ]
+  },
+  {
+    "cmd": [
+      "[START_DIR]/cipd/ninja",
+      "-C",
+      "[START_DIR]/gn/out"
+    ],
+    "cwd": "[START_DIR]/gn",
+    "name": "release.build.ninja",
+    "~followup_annotations": [
+      "@@@STEP_NEST_LEVEL@2@@@"
+    ]
+  },
+  {
+    "cmd": [
+      "sudo",
+      "xcode-select",
+      "--reset"
+    ],
+    "cwd": "[START_DIR]/gn",
+    "infra_step": true,
+    "name": "release.build.reset XCode",
+    "~followup_annotations": [
+      "@@@STEP_NEST_LEVEL@2@@@"
+    ]
+  },
+  {
+    "cmd": [
+      "[START_DIR]/gn/out/gn_unittests"
+    ],
+    "name": "release.test",
+    "~followup_annotations": [
+      "@@@STEP_NEST_LEVEL@1@@@"
+    ]
+  },
+  {
+    "name": "$result",
+    "recipe_result": null,
+    "status_code": 0
+  }
+]
\ No newline at end of file
diff --git a/infra/recipes/gn.expected/cq.json b/infra/recipes/gn.expected/cq_win.json
similarity index 93%
rename from infra/recipes/gn.expected/cq.json
rename to infra/recipes/gn.expected/cq_win.json
index e9b8b25..57dea98 100644
--- a/infra/recipes/gn.expected/cq.json
+++ b/infra/recipes/gn.expected/cq_win.json
@@ -113,7 +113,7 @@
       "cipd.bat",
       "ensure",
       "-root",
-      "[START_DIR]\\cipd\\windows_sdk",
+      "[CACHE]\\windows_sdk",
       "-ensure-file",
       "chrome_internal/third_party/sdk/windows uploaded:2018-06-13",
       "-json-output",
@@ -142,7 +142,7 @@
       "python",
       "-u",
       "\nimport shutil\nimport sys\nshutil.copy(sys.argv[1], sys.argv[2])\n",
-      "[START_DIR]\\cipd\\windows_sdk\\win_sdk\\bin\\SetEnv.x64.json",
+      "[CACHE]\\windows_sdk\\win_sdk\\bin\\SetEnv.x64.json",
       "/path/to/tmp/json"
     ],
     "cwd": "[START_DIR]\\gn",
@@ -180,11 +180,11 @@
     ],
     "cwd": "[START_DIR]\\gn",
     "env": {
-      "VSINSTALLDIR": "[START_DIR]\\cipd\\windows_sdk"
+      "VSINSTALLDIR": "[CACHE]\\windows_sdk"
     },
     "env_prefixes": {
       "PATH": [
-        "[START_DIR]\\cipd\\windows_sdk\\win_sdk\\bin\\x64"
+        "[CACHE]\\windows_sdk\\win_sdk\\bin\\x64"
       ]
     },
     "name": "debug.build.generate",
@@ -200,11 +200,11 @@
     ],
     "cwd": "[START_DIR]\\gn",
     "env": {
-      "VSINSTALLDIR": "[START_DIR]\\cipd\\windows_sdk"
+      "VSINSTALLDIR": "[CACHE]\\windows_sdk"
     },
     "env_prefixes": {
       "PATH": [
-        "[START_DIR]\\cipd\\windows_sdk\\win_sdk\\bin\\x64"
+        "[CACHE]\\windows_sdk\\win_sdk\\bin\\x64"
       ]
     },
     "name": "debug.build.ninja",
@@ -251,7 +251,7 @@
       "cipd.bat",
       "ensure",
       "-root",
-      "[START_DIR]\\cipd\\windows_sdk",
+      "[CACHE]\\windows_sdk",
       "-ensure-file",
       "chrome_internal/third_party/sdk/windows uploaded:2018-06-13",
       "-json-output",
@@ -280,7 +280,7 @@
       "python",
       "-u",
       "\nimport shutil\nimport sys\nshutil.copy(sys.argv[1], sys.argv[2])\n",
-      "[START_DIR]\\cipd\\windows_sdk\\win_sdk\\bin\\SetEnv.x64.json",
+      "[CACHE]\\windows_sdk\\win_sdk\\bin\\SetEnv.x64.json",
       "/path/to/tmp/json"
     ],
     "cwd": "[START_DIR]\\gn",
@@ -317,11 +317,11 @@
     ],
     "cwd": "[START_DIR]\\gn",
     "env": {
-      "VSINSTALLDIR": "[START_DIR]\\cipd\\windows_sdk"
+      "VSINSTALLDIR": "[CACHE]\\windows_sdk"
     },
     "env_prefixes": {
       "PATH": [
-        "[START_DIR]\\cipd\\windows_sdk\\win_sdk\\bin\\x64"
+        "[CACHE]\\windows_sdk\\win_sdk\\bin\\x64"
       ]
     },
     "name": "release.build.generate",
@@ -337,11 +337,11 @@
     ],
     "cwd": "[START_DIR]\\gn",
     "env": {
-      "VSINSTALLDIR": "[START_DIR]\\cipd\\windows_sdk"
+      "VSINSTALLDIR": "[CACHE]\\windows_sdk"
     },
     "env_prefixes": {
       "PATH": [
-        "[START_DIR]\\cipd\\windows_sdk\\win_sdk\\bin\\x64"
+        "[CACHE]\\windows_sdk\\win_sdk\\bin\\x64"
       ]
     },
     "name": "release.build.ninja",
diff --git a/infra/recipes/gn.py b/infra/recipes/gn.py
index 0a88862..86eae2d 100644
--- a/infra/recipes/gn.py
+++ b/infra/recipes/gn.py
@@ -17,6 +17,7 @@
     'recipe_engine/python',
     'recipe_engine/raw_io',
     'recipe_engine/step',
+    'macos_sdk',
     'windows_sdk',
 ]
 
@@ -83,7 +84,7 @@
     with api.step.nest(config['name']):
       with api.step.nest('build'):
         with api.context(
-            env=env, cwd=src_dir), api.windows_sdk(enabled=api.platform.is_win):
+            env=env, cwd=src_dir), api.macos_sdk(), api.windows_sdk():
           api.python(
               'generate', src_dir.join('build', 'gen.py'), args=config['args'])
 
@@ -149,16 +150,19 @@
 def GenTests(api):
   REVISION = 'aaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaa'
 
-  yield (api.test('ci') + api.platform.name('win') + api.buildbucket.ci_build(
-      git_repo='gn.googlesource.com/gn',
-      revision=REVISION,
-  ))
+  for platform in ('linux', 'mac', 'win'):
+    yield (api.test('ci_' + platform) + api.platform.name(platform) +
+           api.buildbucket.ci_build(
+               git_repo='gn.googlesource.com/gn',
+               revision=REVISION,
+           ))
 
-  yield (api.test('cq') + api.platform.name('win') + api.buildbucket.try_build(
-      gerrit_host='gn-review.googlesource.com',
-      change_number=1000,
-      patch_set=1,
-  ))
+    yield (api.test('cq_' + platform) + api.platform.name(platform) +
+           api.buildbucket.try_build(
+               gerrit_host='gn-review.googlesource.com',
+               change_number=1000,
+               patch_set=1,
+           ))
 
   yield (api.test('cipd_exists') + api.buildbucket.ci_build(
       project='infra-internal',