TL;DR - why do imports return undefined? Especially for native Node modules like path?

I have a very small test application, built with Vite, that has a single endpoint in the /api directory. I created this just to play around with Vite + Vercel.

I have only 2 module imports for my endpoint - path and fs-extra. Both are returning as undefined. I was getting cannot read join of undefined errors with the path module, so I wrapped everything in a try/catch just to see if the endpoint responds. It does. See my code below.

import type {VercelRequest, VercelResponse} from '@vercel/node'
import path from 'node:path' // I've also tried 'path'
import fs from 'fs-extra'

export default function handler(req: VercelRequest, res: VercelResponse) {
  // Both of these log 'undefined' on my Vercel dashboard for function logs.
  console.log('path module:', path)
  console.log('fs module:', fs)

  try {
    // https://vercel.com/guides/how-can-i-use-files-in-serverless-functions
    const pathFromProjectRootToFile = '/api/usersData.json'
    const usersDataFilePath = path.join( // THIS IS WHERE THE ERROR HAPPENS 🙃
      process.cwd(),
      pathFromProjectRootToFile
    )
    const usersData = fs.readJSONSync(usersDataFilePath)
    res.json({users: usersData})
  } catch (e) {
    res.json({error: errorToObject(e as Error)})
  }
}

function errorToObject(err?: Error): Record<string, string> | null {
  if (!err || !(err instanceof Error)) return null

  const obj: Record<string, string> = {}

  Object.getOwnPropertyNames(err).forEach(prop => {
    const value = err[prop as keyof Error]

    if (typeof value !== 'string') return

    obj[prop] = value
  })

  return obj
}

As an aside, instead of node:path I also tried just path, but same thing - undefined. And I do have fs-extra as a dependency in my package.json.