How to make ES modules import from a Lambda layer work?

Question

I have a lambda function in node v14 that imports AWS SDK v3 from a lambda layer.

In my function I can use my node modules from the layer only if I use CommonJS syntax:

const { parseUrl } = require('@aws-sdk/url-parser');

Using ES modules doesn't work.

import { parseUrl } from '@aws-sdk/url-parser';

It will throw an error: "errorMessage": "Cannot find package '@aws-sdk/url-parser' imported from /var/task/index.js\nDid you mean to import @aws-sdk/url-parser/dist-cjs/index.js?"

It should work. I have "type": "module" in package.json and locally the import works. It also starts working when I specify the full path to cjs index file:

import { parseUrl } from '/opt/nodejs/node_modules/@aws-sdk/url-parser/dist-cjs/index.js';

Which is really weird.

I checked NODE_PATH and /opt/nodejs/node_modules is there so I don't know where the problem is.

The full implementation is here so you can replicate the error: https://github.com/simon-q/lambda-layer-es-modules-error

Is it something broken in lambda layers or am I doing something wrong? I would really appreciate any help.

Thanks.