Error running vercel dev locally: No fetch handler exported from file:///.../packagephobia/src/server.ts

[JoshuaKGoldberg]

After running npm i and following the instructions in CONTRIBUTING.md, including getting redis running with Docker:

$ vercel dev
Vercel CLI 56.5.0 (Node.js 24.3.0)
> Ready! Available at http://localhost:3000
NODE_ENV: development
isProd:  false
TMPDIR:  /var/folders/1_/pn8_jg_93cqdnkyswmmr5sxm0000gn/T/
HOME:  /var/folders/1_/pn8_jg_93cqdnkyswmmr5sxm0000gn/T/
◆ Server handler: No fetch handler exported from file:///Users/josh/repos/packagephobia/src/server.ts
◇ Static files:   ./public/

➜ Listening on: http://127.0.0.1:51327/
[8:49:02 AM] GET http://127.0.0.1:51327/ [501] (2.25ms)

Visiting http://localhost:3000 indeed shows:

I tried this with a few versions using npx -y vercel@... dev:

• 54, 55: same Server handler: No fetch handler exported
• 50, 53: LambdaError: Unable to import module 'src/server'

🤷

[styfle]

Thats a new error I've never seen before.

It works for me

npm i -g vercel@latest
vercel dev
Vercel CLI 58.0.0 (Node.js 22.23.1)
> Ready! Available at http://localhost:3000

Perhaps there is an outdated transitive dependency? Because the error looks like its coming from @vercel/fun here https://github.com/vercel/fun/blob/f317e0d3ceadb8c9eb7af9123c9409a9ecb91fcf/src/runtimes/nodejs/bootstrap.ts#L203 but I dont think vercel cli uses that anymore 🤔

[styfle]

Ah it was a change to how server.ts is treated.

Fixed in #1105, thanks!