@apphosting/build@0.1.7 missing `yaml` in package.json dependencies

[philemonkipngetich]

[REQUIRED] Environment info

firebase-tools: 15.17.0

Platform: Windows

[REQUIRED] Test case

Any project using Firebase Functions. Run:

firebase deploy --only functions

[REQUIRED] Steps to reproduce

1. Install firebase-tools globally
2. In any Firebase Functions project, run:

   firebase deploy --only functions --debug

3. The CLI crashes immediately on startup before deployment even begins

[REQUIRED] Expected behavior

firebase deploy --only functions should execute successfully without module resolution errors.

[REQUIRED] Actual behavior

The CLI crashes immediately with:

Error: Cannot find module 'yaml'
Require stack:
- ...\node_modules\@apphosting\build\dist\index.js
- ...\node_modules\firebase-tools\lib\apphosting\localbuilds.js
- ...\node_modules\firebase-tools\lib\deploy\apphosting\prepare.js
- ...\node_modules\firebase-tools\lib\deploy\apphosting\index.js
- ...\node_modules\firebase-tools\lib\deploy\index.js
- ...\node_modules\firebase-tools\lib\commands\deploy.js
- ...\node_modules\firebase-tools\lib\commands\index.js
- ...\node_modules\firebase-tools\lib\index.js
- ...\node_modules\firebase-tools\lib\bin\cli.js
- ...\node_modules\firebase-tools\lib\bin\firebase.js

Error: An unexpected error has occurred.

Root cause:

@apphosting/build@0.1.7 calls require("yaml") in dist/index.js at line 13:

const yaml_1 = require("yaml");

However, yaml is not declared as a dependency in @apphosting/build's package.json. Its declared dependencies are only:

{
  "dependencies": {
    "@apphosting/common": "^0.0.9",
    "@npmcli/promise-spawn": "^3.0.0",
    "colorette": "^2.0.20",
    "commander": "^11.1.0",
    "npm-pick-manifest": "^9.0.0",
    "ts-node": "^10.9.1"
  }
}

yaml is a dependency of firebase-tools itself, and @apphosting/build currently only resolves it by accidentally inheriting it through firebase-tools's node_modules via hoisting. This is not guaranteed behavior per the Node.js module resolution specification.

Suggested fix:

Add yaml to @apphosting/build's dependencies in its package.json:

{
  "dependencies": {
    "yaml": "^2.0.0"
  }
}

[aalej]

Hey @philemonkipngetich, thanks for the detailed report. I'm trying to reproduce this issue, but no errors we're raised when I ran firebase deploy --only functions. The steps I took were:

1. Run firebase init functions
   • Select JavaScript
2. Uncomment the sample onRequest() function
3. Run firebase deploy --only functions

deploy output

$ firebase deploy --only functions

=== Deploying to 'PROJECT_ID'...

i  deploying functions
i  functions: preparing codebase default for deployment
i  functions: ensuring required API cloudfunctions.googleapis.com is enabled...
i  functions: ensuring required API cloudbuild.googleapis.com is enabled...
i  artifactregistry: ensuring required API artifactregistry.googleapis.com is enabled...
i  functions: Loading and analyzing source code for codebase default to determine what to deploy
Serving at port 8556

i  extensions: ensuring required API firebaseextensions.googleapis.com is enabled...
i  functions: preparing functions directory for uploading...
i  functions: packaged /workspaces/codespaces-blank/functions (70.68 KB) for uploading
i  functions: ensuring required API run.googleapis.com is enabled...
i  functions: ensuring required API eventarc.googleapis.com is enabled...
i  functions: ensuring required API pubsub.googleapis.com is enabled...
i  functions: ensuring required API storage.googleapis.com is enabled...
i  functions: generating the service identity for pubsub.googleapis.com...
i  functions: generating the service identity for eventarc.googleapis.com...
✔  functions: functions source uploaded successfully
i  functions: creating Node.js 24 (2nd Gen) function helloWorld(us-central1)...
✔  functions[helloWorld(us-central1)] Successful create operation.
Function URL (helloWorld(us-central1)): https://us-central1-PROJECT_ID.cloudfunctions.net/helloWorld

✔  Deploy complete!

Project Console: https://console.firebase.google.com/project/PROJECT_ID/overview

I'll check this with our engineering team, but could you let us know which version of npm and Node.js you are using to help us reproduce the issue? Could you also share the output of firebase experiments:list?

[philemonkipngetich]

Thanks for checking.

I think the difference may be that I installed Firebase CLI globally using pnpm v11 instead of npm.

node -v
v24.15.0

pnpm -v
11.1.1

firebase --version
15.17.0

Firebase CLI was installed globally with:

pnpm add -g firebase-tools

Reproduction

The crash happens before deployment starts when running:

firebase deploy --only functions 

Error

Error: Cannot find module 'yaml'
Require stack:
- ...\node_modules\@apphosting\build\dist\index.js
- ...\node_modules\firebase-tools\lib\apphosting\localbuilds.js
- ...\node_modules\firebase-tools\lib\deploy\apphosting\prepare.js
- ...\node_modules\firebase-tools\lib\deploy\apphosting\index.js
- ...\node_modules\firebase-tools\lib\deploy\index.js
- ...\node_modules\firebase-tools\lib\commands\deploy.js
- ...\node_modules\firebase-tools\lib\commands\index.js
- ...\node_modules\firebase-tools\lib\index.js
- ...\node_modules\firebase-tools\lib\bin\cli.js
- ...\node_modules\firebase-tools\lib\bin\firebase.js

The error originates from:

@apphosting/build/dist/index.js

which imports:

const yaml_1 = require("yaml");

However, yaml does not appear to be declared as a direct dependency of @apphosting/build.

firebase experiments:list

Enabled:
- functionsv2deployoptimizations
- pintags
- apphosting
- genkit
- mcp
- fdcift
- fdcwebhooks
- fdcrealtime

Disabled:
- deletegcfartifacts
- legacyRuntimeConfigCommands
- dartfunctions
- webframeworks
- appsinit
- mcpalpha
- mcpapps
- apptesting

This may be reproducible specifically with pnpm v11 global installs, since pnpm v11 isolates undeclared transitive dependencies more strictly than npm-style hoisting.

[aalej]

Thanks for the additional info! I was able to reproduce the issue when installing using pnpm v11. I'll share this with our engineering team.