I used to deploy express apps written in JS in the past with no problem, but now when I try deploying an express application written in TypeScript my serverless function crashes and I get the following error.

Error: Cannot find package 'express' imported from /var/task/app.js
    at new NodeError (node:internal/errors:405:5)
    at packageResolve (node:internal/modules/esm/resolve:892:9)
    at moduleResolve (node:internal/modules/esm/resolve:985:20)
    at moduleResolveWithNodePath (node:internal/modules/esm/resolve:936:12)
    at defaultResolve (node:internal/modules/esm/resolve:1178:79)
    at nextResolve (node:internal/modules/esm/loader:163:28)
    at ESMLoader.resolve (node:internal/modules/esm/loader:835:30)
    at ESMLoader.getModuleJob (node:internal/modules/esm/loader:424:18)
    at ModuleWrap.<anonymous> (node:internal/modules/esm/module_job:77:40)
    at link (node:internal/modules/esm/module_job:76:36) {
  code: 'ERR_MODULE_NOT_FOUND'
}
...

This is how my vercel.json file looks.

{
  "builds": [
    {
      "src": "*.ts",
      "use": "@vercel/node"
    }
  ],
  "rewrites": [
    {
      "source": "/(.*)",
      "destination": "app.ts"
    }
  ]
}

How do I fix this issue?

~[#10713](https://github.com/vercel/vercel/discussions/10713)