(I think this is a feature request, more than a bug 🤔)

Is your feature request related to a problem? Please describe.

When upgrading next from 12.0.8 to 12.0.9, API routes started to return a generic 503 from CloudFront.

• Update: I'm seeing the same error message that @jakubriedl posted ¹

TypeError: Cannot read property 'headers' of undefined
    at Object.apiResolver (/var/task/chunks/89.js:10564:43)
    at Module.<anonymous> (/var/task/chunks/89.js:6094:34)

A barebones API route (/api/health.ts) would return a generic 503 CloudFront error

import { NextApiHandler } from "next";

const handler: NextApiHandler = async (req, res) => {
  return res.status(200).send("OK");
};

export default handler;

Describe the solution you'd like

For these to just work with next >= 12.0.9 🙏

    "@sls-next/cdk-construct": "3.7.0-alpha.7",
    "@sls-next/lambda-at-edge": "3.7.0-alpha.7",

Describe alternatives you've considered

Pin next to 12.0.8

Additional context

vercel/next.js@v12.0.8...v12.0.9