using node-postgres (`pg`) in AWS Lambda

lambda.js

import λ from "apex.js";
import { Pool } from "pg";

// connection details inherited from environment
const pool = new Pool({
    max: 1,
    min: 0,
    idleTimeoutMillis: 120000,
    connectionTimeoutMillis: 10000
});

export default function λ(async (event, context) => {
  // https://github.com/brianc/node-postgres/issues/930#issuecomment-230362178
  context.callbackWaitsForEmptyEventLoop = false; // !important to reuse pool
  
  const client = await pool.connect();
  
  try {
    await client.query("SELECT NOW()");
  } finally {
    // https://github.com/brianc/node-postgres/issues/1180#issuecomment-270589769
    client.release(true);
  }
});

This is perfect.
For anyone that may work with this, please don't forget:

finally{
    client.release();
}

Without that, after ~10 requests, your Lambda will throw an error.