diff --git a/recipes/infra/ci_yaml.expected/flutter.monorepo.json b/recipes/infra/ci_yaml.expected/flutter.monorepo.json
new file mode 100644
index 0000000..897fb28
--- /dev/null
+++ b/recipes/infra/ci_yaml.expected/flutter.monorepo.json
@@ -0,0 +1,1478 @@
+[
+  {
+    "cmd": [],
+    "name": "Checkout flutter/flutter"
+  },
+  {
+    "cmd": [
+      "python3",
+      "-u",
+      "RECIPE_MODULE[depot_tools::git]/resources/git_setup.py",
+      "--path",
+      "[START_DIR]/flutter",
+      "--url",
+      "https://flutter.googlesource.com/mirrors/flutter"
+    ],
+    "luci_context": {
+      "realm": {
+        "name": "project:prod"
+      },
+      "resultdb": {
+        "current_invocation": {
+          "name": "invocations/build:8945511751514863184",
+          "update_token": "token"
+        },
+        "hostname": "rdbhost"
+      }
+    },
+    "name": "Checkout flutter/flutter.git setup",
+    "~followup_annotations": [
+      "@@@STEP_NEST_LEVEL@1@@@"
+    ]
+  },
+  {
+    "cmd": [
+      "git",
+      "fetch",
+      "origin",
+      "master",
+      "--recurse-submodules",
+      "--progress",
+      "--tags"
+    ],
+    "cwd": "[START_DIR]/flutter",
+    "env": {
+      "PATH": "RECIPE_REPO[depot_tools]:<PATH>"
+    },
+    "infra_step": true,
+    "luci_context": {
+      "realm": {
+        "name": "project:prod"
+      },
+      "resultdb": {
+        "current_invocation": {
+          "name": "invocations/build:8945511751514863184",
+          "update_token": "token"
+        },
+        "hostname": "rdbhost"
+      }
+    },
+    "name": "Checkout flutter/flutter.git fetch",
+    "~followup_annotations": [
+      "@@@STEP_NEST_LEVEL@1@@@"
+    ]
+  },
+  {
+    "cmd": [
+      "git",
+      "checkout",
+      "-f",
+      "FETCH_HEAD"
+    ],
+    "cwd": "[START_DIR]/flutter",
+    "infra_step": true,
+    "luci_context": {
+      "realm": {
+        "name": "project:prod"
+      },
+      "resultdb": {
+        "current_invocation": {
+          "name": "invocations/build:8945511751514863184",
+          "update_token": "token"
+        },
+        "hostname": "rdbhost"
+      }
+    },
+    "name": "Checkout flutter/flutter.git checkout",
+    "~followup_annotations": [
+      "@@@STEP_NEST_LEVEL@1@@@"
+    ]
+  },
+  {
+    "cmd": [
+      "git",
+      "rev-parse",
+      "HEAD"
+    ],
+    "cwd": "[START_DIR]/flutter",
+    "infra_step": true,
+    "luci_context": {
+      "realm": {
+        "name": "project:prod"
+      },
+      "resultdb": {
+        "current_invocation": {
+          "name": "invocations/build:8945511751514863184",
+          "update_token": "token"
+        },
+        "hostname": "rdbhost"
+      }
+    },
+    "name": "Checkout flutter/flutter.read revision",
+    "~followup_annotations": [
+      "@@@STEP_NEST_LEVEL@1@@@",
+      "@@@STEP_TEXT@<br/>checked out 'deadbeef'<br/>@@@",
+      "@@@SET_BUILD_PROPERTY@got_revision@\"deadbeef\"@@@"
+    ]
+  },
+  {
+    "cmd": [
+      "git",
+      "clean",
+      "-f",
+      "-d",
+      "-x"
+    ],
+    "cwd": "[START_DIR]/flutter",
+    "infra_step": true,
+    "luci_context": {
+      "realm": {
+        "name": "project:prod"
+      },
+      "resultdb": {
+        "current_invocation": {
+          "name": "invocations/build:8945511751514863184",
+          "update_token": "token"
+        },
+        "hostname": "rdbhost"
+      }
+    },
+    "name": "Checkout flutter/flutter.git clean",
+    "~followup_annotations": [
+      "@@@STEP_NEST_LEVEL@1@@@"
+    ]
+  },
+  {
+    "cmd": [
+      "git",
+      "submodule",
+      "sync"
+    ],
+    "cwd": "[START_DIR]/flutter",
+    "infra_step": true,
+    "luci_context": {
+      "realm": {
+        "name": "project:prod"
+      },
+      "resultdb": {
+        "current_invocation": {
+          "name": "invocations/build:8945511751514863184",
+          "update_token": "token"
+        },
+        "hostname": "rdbhost"
+      }
+    },
+    "name": "Checkout flutter/flutter.submodule sync",
+    "~followup_annotations": [
+      "@@@STEP_NEST_LEVEL@1@@@"
+    ]
+  },
+  {
+    "cmd": [
+      "git",
+      "submodule",
+      "update",
+      "--init",
+      "--recursive"
+    ],
+    "cwd": "[START_DIR]/flutter",
+    "infra_step": true,
+    "luci_context": {
+      "realm": {
+        "name": "project:prod"
+      },
+      "resultdb": {
+        "current_invocation": {
+          "name": "invocations/build:8945511751514863184",
+          "update_token": "token"
+        },
+        "hostname": "rdbhost"
+      }
+    },
+    "name": "Checkout flutter/flutter.submodule update",
+    "~followup_annotations": [
+      "@@@STEP_NEST_LEVEL@1@@@"
+    ]
+  },
+  {
+    "cmd": [],
+    "name": "Checkout flutter/cocoon"
+  },
+  {
+    "cmd": [
+      "python3",
+      "-u",
+      "RECIPE_MODULE[depot_tools::git]/resources/git_setup.py",
+      "--path",
+      "[START_DIR]/cocoon",
+      "--url",
+      "https://flutter.googlesource.com/mirrors/cocoon"
+    ],
+    "luci_context": {
+      "realm": {
+        "name": "project:prod"
+      },
+      "resultdb": {
+        "current_invocation": {
+          "name": "invocations/build:8945511751514863184",
+          "update_token": "token"
+        },
+        "hostname": "rdbhost"
+      }
+    },
+    "name": "Checkout flutter/cocoon.git setup",
+    "~followup_annotations": [
+      "@@@STEP_NEST_LEVEL@1@@@"
+    ]
+  },
+  {
+    "cmd": [
+      "git",
+      "fetch",
+      "origin",
+      "main",
+      "--recurse-submodules",
+      "--progress",
+      "--tags"
+    ],
+    "cwd": "[START_DIR]/cocoon",
+    "env": {
+      "PATH": "RECIPE_REPO[depot_tools]:<PATH>"
+    },
+    "infra_step": true,
+    "luci_context": {
+      "realm": {
+        "name": "project:prod"
+      },
+      "resultdb": {
+        "current_invocation": {
+          "name": "invocations/build:8945511751514863184",
+          "update_token": "token"
+        },
+        "hostname": "rdbhost"
+      }
+    },
+    "name": "Checkout flutter/cocoon.git fetch",
+    "~followup_annotations": [
+      "@@@STEP_NEST_LEVEL@1@@@"
+    ]
+  },
+  {
+    "cmd": [
+      "git",
+      "checkout",
+      "-f",
+      "FETCH_HEAD"
+    ],
+    "cwd": "[START_DIR]/cocoon",
+    "infra_step": true,
+    "luci_context": {
+      "realm": {
+        "name": "project:prod"
+      },
+      "resultdb": {
+        "current_invocation": {
+          "name": "invocations/build:8945511751514863184",
+          "update_token": "token"
+        },
+        "hostname": "rdbhost"
+      }
+    },
+    "name": "Checkout flutter/cocoon.git checkout",
+    "~followup_annotations": [
+      "@@@STEP_NEST_LEVEL@1@@@"
+    ]
+  },
+  {
+    "cmd": [
+      "git",
+      "rev-parse",
+      "HEAD"
+    ],
+    "cwd": "[START_DIR]/cocoon",
+    "infra_step": true,
+    "luci_context": {
+      "realm": {
+        "name": "project:prod"
+      },
+      "resultdb": {
+        "current_invocation": {
+          "name": "invocations/build:8945511751514863184",
+          "update_token": "token"
+        },
+        "hostname": "rdbhost"
+      }
+    },
+    "name": "Checkout flutter/cocoon.read revision",
+    "~followup_annotations": [
+      "@@@STEP_NEST_LEVEL@1@@@",
+      "@@@STEP_TEXT@<br/>checked out 'deadbeef'<br/>@@@",
+      "@@@SET_BUILD_PROPERTY@got_revision@\"deadbeef\"@@@"
+    ]
+  },
+  {
+    "cmd": [
+      "git",
+      "clean",
+      "-f",
+      "-d",
+      "-x"
+    ],
+    "cwd": "[START_DIR]/cocoon",
+    "infra_step": true,
+    "luci_context": {
+      "realm": {
+        "name": "project:prod"
+      },
+      "resultdb": {
+        "current_invocation": {
+          "name": "invocations/build:8945511751514863184",
+          "update_token": "token"
+        },
+        "hostname": "rdbhost"
+      }
+    },
+    "name": "Checkout flutter/cocoon.git clean",
+    "~followup_annotations": [
+      "@@@STEP_NEST_LEVEL@1@@@"
+    ]
+  },
+  {
+    "cmd": [
+      "git",
+      "submodule",
+      "sync"
+    ],
+    "cwd": "[START_DIR]/cocoon",
+    "infra_step": true,
+    "luci_context": {
+      "realm": {
+        "name": "project:prod"
+      },
+      "resultdb": {
+        "current_invocation": {
+          "name": "invocations/build:8945511751514863184",
+          "update_token": "token"
+        },
+        "hostname": "rdbhost"
+      }
+    },
+    "name": "Checkout flutter/cocoon.submodule sync",
+    "~followup_annotations": [
+      "@@@STEP_NEST_LEVEL@1@@@"
+    ]
+  },
+  {
+    "cmd": [
+      "git",
+      "submodule",
+      "update",
+      "--init",
+      "--recursive"
+    ],
+    "cwd": "[START_DIR]/cocoon",
+    "infra_step": true,
+    "luci_context": {
+      "realm": {
+        "name": "project:prod"
+      },
+      "resultdb": {
+        "current_invocation": {
+          "name": "invocations/build:8945511751514863184",
+          "update_token": "token"
+        },
+        "hostname": "rdbhost"
+      }
+    },
+    "name": "Checkout flutter/cocoon.submodule update",
+    "~followup_annotations": [
+      "@@@STEP_NEST_LEVEL@1@@@"
+    ]
+  },
+  {
+    "cmd": [],
+    "name": "Checkout flutter/infra"
+  },
+  {
+    "cmd": [
+      "python3",
+      "-u",
+      "RECIPE_MODULE[depot_tools::git]/resources/git_setup.py",
+      "--path",
+      "[START_DIR]/infra",
+      "--url",
+      "https://flutter.googlesource.com/infra"
+    ],
+    "luci_context": {
+      "realm": {
+        "name": "project:prod"
+      },
+      "resultdb": {
+        "current_invocation": {
+          "name": "invocations/build:8945511751514863184",
+          "update_token": "token"
+        },
+        "hostname": "rdbhost"
+      }
+    },
+    "name": "Checkout flutter/infra.git setup",
+    "~followup_annotations": [
+      "@@@STEP_NEST_LEVEL@1@@@"
+    ]
+  },
+  {
+    "cmd": [
+      "git",
+      "fetch",
+      "origin",
+      "main",
+      "--recurse-submodules",
+      "--progress",
+      "--tags"
+    ],
+    "cwd": "[START_DIR]/infra",
+    "env": {
+      "PATH": "RECIPE_REPO[depot_tools]:<PATH>"
+    },
+    "infra_step": true,
+    "luci_context": {
+      "realm": {
+        "name": "project:prod"
+      },
+      "resultdb": {
+        "current_invocation": {
+          "name": "invocations/build:8945511751514863184",
+          "update_token": "token"
+        },
+        "hostname": "rdbhost"
+      }
+    },
+    "name": "Checkout flutter/infra.git fetch",
+    "~followup_annotations": [
+      "@@@STEP_NEST_LEVEL@1@@@"
+    ]
+  },
+  {
+    "cmd": [
+      "git",
+      "checkout",
+      "-f",
+      "FETCH_HEAD"
+    ],
+    "cwd": "[START_DIR]/infra",
+    "infra_step": true,
+    "luci_context": {
+      "realm": {
+        "name": "project:prod"
+      },
+      "resultdb": {
+        "current_invocation": {
+          "name": "invocations/build:8945511751514863184",
+          "update_token": "token"
+        },
+        "hostname": "rdbhost"
+      }
+    },
+    "name": "Checkout flutter/infra.git checkout",
+    "~followup_annotations": [
+      "@@@STEP_NEST_LEVEL@1@@@"
+    ]
+  },
+  {
+    "cmd": [
+      "git",
+      "rev-parse",
+      "HEAD"
+    ],
+    "cwd": "[START_DIR]/infra",
+    "infra_step": true,
+    "luci_context": {
+      "realm": {
+        "name": "project:prod"
+      },
+      "resultdb": {
+        "current_invocation": {
+          "name": "invocations/build:8945511751514863184",
+          "update_token": "token"
+        },
+        "hostname": "rdbhost"
+      }
+    },
+    "name": "Checkout flutter/infra.read revision",
+    "~followup_annotations": [
+      "@@@STEP_NEST_LEVEL@1@@@",
+      "@@@STEP_TEXT@<br/>checked out 'deadbeef'<br/>@@@",
+      "@@@SET_BUILD_PROPERTY@got_revision@\"deadbeef\"@@@"
+    ]
+  },
+  {
+    "cmd": [
+      "git",
+      "clean",
+      "-f",
+      "-d",
+      "-x"
+    ],
+    "cwd": "[START_DIR]/infra",
+    "infra_step": true,
+    "luci_context": {
+      "realm": {
+        "name": "project:prod"
+      },
+      "resultdb": {
+        "current_invocation": {
+          "name": "invocations/build:8945511751514863184",
+          "update_token": "token"
+        },
+        "hostname": "rdbhost"
+      }
+    },
+    "name": "Checkout flutter/infra.git clean",
+    "~followup_annotations": [
+      "@@@STEP_NEST_LEVEL@1@@@"
+    ]
+  },
+  {
+    "cmd": [
+      "git",
+      "submodule",
+      "sync"
+    ],
+    "cwd": "[START_DIR]/infra",
+    "infra_step": true,
+    "luci_context": {
+      "realm": {
+        "name": "project:prod"
+      },
+      "resultdb": {
+        "current_invocation": {
+          "name": "invocations/build:8945511751514863184",
+          "update_token": "token"
+        },
+        "hostname": "rdbhost"
+      }
+    },
+    "name": "Checkout flutter/infra.submodule sync",
+    "~followup_annotations": [
+      "@@@STEP_NEST_LEVEL@1@@@"
+    ]
+  },
+  {
+    "cmd": [
+      "git",
+      "submodule",
+      "update",
+      "--init",
+      "--recursive"
+    ],
+    "cwd": "[START_DIR]/infra",
+    "infra_step": true,
+    "luci_context": {
+      "realm": {
+        "name": "project:prod"
+      },
+      "resultdb": {
+        "current_invocation": {
+          "name": "invocations/build:8945511751514863184",
+          "update_token": "token"
+        },
+        "hostname": "rdbhost"
+      }
+    },
+    "name": "Checkout flutter/infra.submodule update",
+    "~followup_annotations": [
+      "@@@STEP_NEST_LEVEL@1@@@"
+    ]
+  },
+  {
+    "cmd": [
+      "cipd",
+      "ensure",
+      "-root",
+      "[START_DIR]/protoc",
+      "-ensure-file",
+      "infra/3pp/tools/protoc/${platform} version:2@3.17.3",
+      "-max-threads",
+      "0",
+      "-json-output",
+      "/path/to/tmp/json"
+    ],
+    "luci_context": {
+      "realm": {
+        "name": "project:prod"
+      },
+      "resultdb": {
+        "current_invocation": {
+          "name": "invocations/build:8945511751514863184",
+          "update_token": "token"
+        },
+        "hostname": "rdbhost"
+      }
+    },
+    "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:2@3.17.3\",@@@",
+      "@@@STEP_LOG_LINE@json.output@        \"package\": \"infra/3pp/tools/protoc/resolved-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": [
+      "git",
+      "rev-parse",
+      "HEAD"
+    ],
+    "cwd": "[START_DIR]/flutter",
+    "infra_step": true,
+    "luci_context": {
+      "realm": {
+        "name": "project:prod"
+      },
+      "resultdb": {
+        "current_invocation": {
+          "name": "invocations/build:8945511751514863184",
+          "update_token": "token"
+        },
+        "hostname": "rdbhost"
+      }
+    },
+    "name": "git rev-parse"
+  },
+  {
+    "cmd": [
+      "[START_DIR]/flutter/bin/flutter",
+      "config",
+      "--clear-features"
+    ],
+    "env": {
+      "ARTIFACT_HUB_REPOSITORY": "artifactregistry://us-maven.pkg.dev/artifact-foundry-prod/maven-3p",
+      "DEPOT_TOOLS": "RECIPE_REPO[depot_tools]",
+      "GIT_BRANCH": "master",
+      "LUCI_BRANCH": "",
+      "LUCI_CI": "True",
+      "LUCI_PR": "",
+      "OS": "linux",
+      "PUB_CACHE": "[START_DIR]/.pub-cache",
+      "REVISION": "12345abcde12345abcde12345abcde12345abcde",
+      "SDK_CHECKOUT_PATH": "[START_DIR]/flutter"
+    },
+    "env_prefixes": {
+      "PATH": [
+        "[START_DIR]/flutter/bin",
+        "[START_DIR]/flutter/bin/cache/dart-sdk/bin"
+      ]
+    },
+    "luci_context": {
+      "realm": {
+        "name": "project:prod"
+      },
+      "resultdb": {
+        "current_invocation": {
+          "name": "invocations/build:8945511751514863184",
+          "update_token": "token"
+        },
+        "hostname": "rdbhost"
+      }
+    },
+    "name": "flutter config --clear-features"
+  },
+  {
+    "cmd": [
+      "flutter",
+      "doctor"
+    ],
+    "cwd": "[START_DIR]/cocoon/app_dart",
+    "env": {
+      "ARTIFACT_HUB_REPOSITORY": "artifactregistry://us-maven.pkg.dev/artifact-foundry-prod/maven-3p",
+      "DEPOT_TOOLS": "RECIPE_REPO[depot_tools]",
+      "GIT_BRANCH": "master",
+      "LUCI_BRANCH": "",
+      "LUCI_CI": "True",
+      "LUCI_PR": "",
+      "OS": "linux",
+      "PUB_CACHE": "[START_DIR]/.pub-cache",
+      "REVISION": "12345abcde12345abcde12345abcde12345abcde",
+      "SDK_CHECKOUT_PATH": "[START_DIR]/flutter"
+    },
+    "env_prefixes": {
+      "PATH": [
+        "[START_DIR]/flutter/bin",
+        "[START_DIR]/flutter/bin/cache/dart-sdk/bin"
+      ]
+    },
+    "luci_context": {
+      "realm": {
+        "name": "project:prod"
+      },
+      "resultdb": {
+        "current_invocation": {
+          "name": "invocations/build:8945511751514863184",
+          "update_token": "token"
+        },
+        "hostname": "rdbhost"
+      }
+    },
+    "name": "flutter doctor"
+  },
+  {
+    "cmd": [
+      "dart",
+      "pub",
+      "get"
+    ],
+    "cwd": "[START_DIR]/cocoon/app_dart",
+    "env": {
+      "ARTIFACT_HUB_REPOSITORY": "artifactregistry://us-maven.pkg.dev/artifact-foundry-prod/maven-3p",
+      "DEPOT_TOOLS": "RECIPE_REPO[depot_tools]",
+      "GIT_BRANCH": "master",
+      "LUCI_BRANCH": "",
+      "LUCI_CI": "True",
+      "LUCI_PR": "",
+      "OS": "linux",
+      "PUB_CACHE": "[START_DIR]/.pub-cache",
+      "REVISION": "12345abcde12345abcde12345abcde12345abcde",
+      "SDK_CHECKOUT_PATH": "[START_DIR]/flutter"
+    },
+    "env_prefixes": {
+      "PATH": [
+        "[START_DIR]/flutter/bin",
+        "[START_DIR]/flutter/bin/cache/dart-sdk/bin"
+      ]
+    },
+    "luci_context": {
+      "realm": {
+        "name": "project:prod"
+      },
+      "resultdb": {
+        "current_invocation": {
+          "name": "invocations/build:8945511751514863184",
+          "update_token": "token"
+        },
+        "hostname": "rdbhost"
+      }
+    },
+    "name": "dart pub get"
+  },
+  {
+    "cmd": [
+      "dart",
+      "[START_DIR]/cocoon/app_dart/bin/generate_jspb.dart",
+      "flutter",
+      "master"
+    ],
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+  {
+    "cmd": [
+      "[START_DIR]/cipd_tool/infra/tools/luci/gerrit/0e548aa33f8113a45a5b3b62201e114e98e63d00f97296912380138f44597b07/gerrit",
+      "change-detail",
+      "-host",
+      "https://flutter-review.googlesource.com",
+      "-input",
+      "{\"change_id\": \"infra~main~I520324b8ea4bfe51bb4d3690983686816663e896\", \"params\": {\"o\": [\"CURRENT_REVISION\", \"DETAILED_ACCOUNTS\"]}}",
+      "-output",
+      "/path/to/tmp/json"
+    ],
+    "cwd": "[START_DIR]/infra",
+    "infra_step": true,
+    "luci_context": {
+      "realm": {
+        "name": "project:prod"
+      },
+      "resultdb": {
+        "current_invocation": {
+          "name": "invocations/build:8945511751514863184",
+          "update_token": "token"
+        },
+        "hostname": "rdbhost"
+      }
+    },
+    "name": "check for completion.check if done (0)",
+    "timeout": 600,
+    "~followup_annotations": [
+      "@@@STEP_NEST_LEVEL@1@@@",
+      "@@@STEP_LOG_LINE@json.output@{@@@",
+      "@@@STEP_LOG_LINE@json.output@  \"current_revision\": \"abc123\",@@@",
+      "@@@STEP_LOG_LINE@json.output@  \"labels\": {@@@",
+      "@@@STEP_LOG_LINE@json.output@    \"Commit-Queue\": {@@@",
+      "@@@STEP_LOG_LINE@json.output@      \"all\": [@@@",
+      "@@@STEP_LOG_LINE@json.output@        {@@@",
+      "@@@STEP_LOG_LINE@json.output@          \"value\": 2@@@",
+      "@@@STEP_LOG_LINE@json.output@        }@@@",
+      "@@@STEP_LOG_LINE@json.output@      ],@@@",
+      "@@@STEP_LOG_LINE@json.output@      \"approved\": {@@@",
+      "@@@STEP_LOG_LINE@json.output@        \"email\": \"roller@fuchsia-service-account.com\"@@@",
+      "@@@STEP_LOG_LINE@json.output@      }@@@",
+      "@@@STEP_LOG_LINE@json.output@    }@@@",
+      "@@@STEP_LOG_LINE@json.output@  },@@@",
+      "@@@STEP_LOG_LINE@json.output@  \"status\": \"MERGED\"@@@",
+      "@@@STEP_LOG_LINE@json.output@}@@@",
+      "@@@STEP_LOG_END@json.output@@@",
+      "@@@STEP_LOG_LINE@json.input@{@@@",
+      "@@@STEP_LOG_LINE@json.input@  \"change_id\": \"infra~main~I520324b8ea4bfe51bb4d3690983686816663e896\",@@@",
+      "@@@STEP_LOG_LINE@json.input@  \"params\": {@@@",
+      "@@@STEP_LOG_LINE@json.input@    \"o\": [@@@",
+      "@@@STEP_LOG_LINE@json.input@      \"CURRENT_REVISION\",@@@",
+      "@@@STEP_LOG_LINE@json.input@      \"DETAILED_ACCOUNTS\"@@@",
+      "@@@STEP_LOG_LINE@json.input@    ]@@@",
+      "@@@STEP_LOG_LINE@json.input@  }@@@",
+      "@@@STEP_LOG_LINE@json.input@}@@@",
+      "@@@STEP_LOG_END@json.input@@@",
+      "@@@STEP_LINK@gerrit link@https://flutter-review.googlesource.com/q/infra~main~I520324b8ea4bfe51bb4d3690983686816663e896@@@"
+    ]
+  },
+  {
+    "name": "$result"
+  }
+]
\ No newline at end of file
diff --git a/recipes/infra/ci_yaml.py b/recipes/infra/ci_yaml.py
index 127cb16..0ea4cd8 100644
--- a/recipes/infra/ci_yaml.py
+++ b/recipes/infra/ci_yaml.py
@@ -76,18 +76,24 @@
     api.step('dart pub get', cmd=['dart', 'pub', 'get'])
     generate_jspb_path = cocoon_path / 'app_dart/bin/generate_jspb.dart'
     config_name = '%s_config.json' % repo
+    # TODO(fujino): verify if we can delete this check
     if git_branch and not _is_default_branch(git_branch):
       config_name = '%s_%s_config.json' % (repo, git_branch)
     infra_config_path = infra_path / f'config/generated/ci_yaml/{config_name}'
 
-    # Generate_jspb
-    jspb_step = api.step(
-        'generate jspb',
-        cmd=['dart', generate_jspb_path, repo, git_ref],
-        stdout=api.raw_io.output_text(add_output_log=True),
-        stderr=api.raw_io.output_text(add_output_log=True)
+    _generate_json(
+        api, generate_jspb_path, repo, git_ref, infra_config_path, False
     )
-    api.file.write_raw('write jspb', infra_config_path, jspb_step.stdout)
+    # If is_fusion, generate for the nested engine .ci.yaml
+    if api.repo_util.is_fusion():
+      _generate_json(
+          api,
+          generate_jspb_path,
+          repo,
+          git_ref,
+          infra_path / f'config/generated/ci_yaml/engine_config.json',
+          True,
+      )
 
   # Roll scheduler.proto
   with api.context(env_prefixes={'PATH': [protoc_path / 'bin']}):
@@ -124,6 +130,21 @@
       )
 
 
+def _generate_json(api, bin_path, repo, git_ref, output_path, is_fusion):
+  cmd = ['dart', bin_path, repo, git_ref]
+  if is_fusion:
+    cmd.append('engine/src/flutter/.ci.yaml')
+  # Generate_jspb for root .ci.yaml
+  jspb_step = api.step(
+      'generate jspb',
+      cmd=cmd,
+      stdout=api.raw_io.output_text(add_output_log=True),
+      stderr=api.raw_io.output_text(add_output_log=True)
+  )
+
+  api.file.write_raw('write jspb', output_path, jspb_step.stdout)
+
+
 def GenTests(api):
   yield api.test(
       'basic',
@@ -138,6 +159,22 @@
       ), api.auto_roller.success()
   )
   yield api.test(
+      'flutter.monorepo',
+      api.buildbucket.ci_build(
+          bucket='prod',
+          git_repo='https://flutter.googlesource.com/mirrors/flutter',
+          revision='abc123'
+      ),
+      api.properties(
+          git_branch='master',
+          git_repo='flutter',
+          is_fusion='true',
+      ), api.repo_util.flutter_environment_data(api.path.start_dir / 'flutter'),
+      api.step_data(
+          'generate jspb', stdout=api.raw_io.output_text('{"hello": "world"}')
+      ), api.auto_roller.success()
+  )
+  yield api.test(
       'release',
       api.buildbucket.ci_build(
           bucket='prod',