We Deleted 300 Lines of Code After Discovering Node.js 22's Hidden Perf Feature

Node.js 22's built-in diagnostics channel is being criminally underused. This week, our team stumbled upon an obscure option that replaced 300 lines of manual logging code, slashed our Lambda execution time by 25%, and saved us $1500 on CloudWatch Logs every month.

Introduction to diagnostics_channel

The diagnostics_channel module in Node.js provides an API for creating custom channels to handle diagnostic events. It allows developers to create channels that can listen to events from various sources, including the Node.js runtime itself. Here's an example of creating a simple channel:

import { createChannel } from 'diagnostics_channel';

const channel = createChannel('my-channel');