What is going wrong with my shared deps in vercel monorepo?

I have a problem with my monorepo, I try to deploy a standard express.js application but the shared dependencies don't load after the deployment, it works in local development.

Has anyone ever encountered this problem with similar configuration while using Vercel CLI for deployments ? Thanks.

Ideas:

I think the trouble probably come from the <rootDir>/services/my-api/vercel.json here (it probably has to wait for more instructions):

"builds": [{ "src": "src/*.ts", "use": "@vercel/node" }]

Other solution:

I think to solve the problem I will use a bundler (webpack or @vercel/ncc) to wrap dependencies into a complete build. I haven't started yet but do you think it could bring other problems? I didn't find any repo on github or gitlab that did this and I think there is probably a reason for that. I'm not sure about the result because I think a build is already done remotely with @vercel/ncc on vercel services.

Encountered error:

On build from vercel service, yarn try to import the package from the yarn packages registry.

18:55:41.470    Retrieving list of deployment files...
18:55:45.058    Downloading 10 deployment files...
18:55:46.336    Analyzing source code...
18:55:46.353    Warning: Due to `builds` existing in your configuration file, the Build and Development Settings defined in your Project Settings will not apply. Learn More: https://vercel.link/unused-build-settings
18:55:47.624    Installing build runtime...
18:55:48.205    Build runtime installed: 581.371ms
18:55:51.010    Looking up build cache...
18:55:51.501    Build cache found. Downloading...
18:55:53.000    Build cache downloaded [19.63 MB]: 1498.987ms
18:55:54.118    Installing dependencies...
18:55:54.466    yarn install v1.22.10
18:55:54.485    info No lockfile found.
18:55:54.490    [1/4] Resolving packages...
18:55:54.700    error An unexpected error occurred: "https://registry.yarnpkg.com/@vercel-monorepo-example%2fcommon: Not found".
18:55:54.700    info If you think this is a bug, please open a bug report with the information provided in "/vercel/path1/yarn-error.log".
18:55:54.701    info Visit https://yarnpkg.com/en/docs/cli/install for documentation about this command.
18:55:54.721    Error: Command "yarn install" exited with 1

My configuration:

Versions:

Tree:

| - packages
  | - common
    | - src
      | - index.ts
    | - package.json
    | - tsconfig.json
| - services
  | - my-api
    | - src
      | - index.ts
    | - package.json
    | - tsconfig.json
    | - vercel.json
| - lerna.json
| - package.json
| - yarn.lock

Files:

# <rootDir>/lerna.json
{
  "npmClient": "yarn",
  "version": "independent",
  "useWorkspaces": true
}

# <rootDir>/package.json
{
  "name": "@vercel-monorepo-example/monorepo",
  "description": "vercel-monorepo-example project root",
  "version": "0.1.0",
  "private": true,
  "workspaces": [
    "packages/*",
    "services/*"
  ]
}

# <rootDir>/packages/common/package.json
{
  "name": "@vercel-monorepo-example/common",
  "description": "vercel-monorepo-example common",
  "version": "0.1.0",
  "main": "src/index.ts",
  "files": ["src"]
}

# <rootDir>/packages/common/tsconfig.json
{
  "compilerOptions": {
    "target": "es5",
    "lib": ["es5", "es6", "esnext"],
    "module": "commonjs",
    "moduleResolution": "node",
    "types": ["node"],
    "sourceMap": true,
    "declaration": true,
    "allowJs": true,
    "skipLibCheck": true,
    "strict": true,
    "removeComments": true,
    "forceConsistentCasingInFileNames": true,
    "noImplicitReturns": true,
    "noImplicitThis": true,
    "esModuleInterop": true,
    "isolatedModules": true,
    "resolveJsonModule": true,
    "outDir": "./dist",
    "baseUrl": ".",
    "paths": {
      "@src/*": ["src/*"]
    }
  },
  "include": ["src/**/*"],
  "exclude": ["node_modules", "dist"]
}

// <rootDir>/packages/common/src/index.ts
export const sayHello = () => console.log('Helloworld!');

# <rootDir>/services/my-api/package.json
{
  "name": "@vercel-monorepo-example/my-api",
  "description": "vercel-monorepo-example api",
  "version": "0.1.0",
  "main": "src/index.ts",
  "dependencies": {
    "@vercel-monorepo-example/common": "0.1.0",
    "express": "^4.17.1"
  },
  "devDependencies": {
    "@types/express": "^4.17.12",
    "@vercel/node": "^1.11.1",
    "typescript": "^4.3.5"
  }
}

# <rootDir>/services/my-api/tsconfig.json
# Use the same configuration than above (@vercel-monorepo-example/common)

# <rootDir>/services/my-api/vercel.json
{
  "version": 2,
  "github": {
    "enabled": false
  },
  "builds": [{ "src": "src/*.ts", "use": "@vercel/node" }],
  "rewrites": [{ "source": "/(.*)", "destination": "/src/index.ts" }]
}

// <rootDir>/services/my-api/src/index.ts
import type { VercelRequest, VercelResponse } from '@vercel/node';
import { sayHello } from '@vercel-monorepo-example/common';

const app = require('express')();

app.get('/', (req: VercelRequest, res: VercelResponse) => {
  sayHello();
  res.status(200);
  res.json({ statusCode: 200 });
});

app.use((req: VercelRequest, res: VercelResponse) => {
  res.status(404);
  res.json({ statusCode: 404 });
});

export default app;

Vercel configuration:

• Build & Development Settings, is set on Other Framework options and the commands are clear.
• Root Directory is set on services/my-api and has Include source files outside of the Root Directory in the Build Step. option checked.