The release of new Node.js versions always brings with it an array of improvements, added functionalities, and other exciting changes. In this post, we’ll take a look at some of the most noteworthy features introduced in Node.js 16 and 17, providing a clearer insight into what developers can now achieve with these versions.

Introduction

Node.js has always maintained a cycle of having two major releases each year, with even-numbered versions being cut in April and odd-numbered ones in October. These releases often include features that cater to developers’ demands for performance, security, and development efficiency. Let’s dive into the specifics!

Node.js 16 Features

1. V8 JavaScript Engine 9.0

Node.js 16 includes an upgrade to V8 9.0, which brings performance tweaks and improvements in compliance with the latest ECMAScript features.

2. Timers Promises API

The Timers Promises API provides an alternative set of timer functions that return Promise objects, simplifying the use of timers in async functions.

import { setTimeout } from 'timers/promises'

async function sampleFunction() {
  await setTimeout(2000)
  console.log('Executed after 2 seconds')
}

sampleFunction()

3. Stable Apple Silicon Binary

Node.js 16 was the first version to provide prebuilt binaries for Apple Silicon, enhancing Node.js’s performance on Apple’s latest line of Macs.

Node.js 17 Features

1. OpenSSL 3.0

Node.js 17 introduced the much-awaited OpenSSL 3.0 upgrade. While this brings numerous cryptography enhancements, it’s worth noting some older or less commonly used crypto modules might no longer be supported.

2. V8 JavaScript Engine 9.5

Continuing the trend of updating the V8 engine, 9.5 adds more ECMAScript features and performance improvements.

3. Throw on Unhandled Promise Rejections

In a move towards safer defaults, Node.js 17 changes the default behavior for unhandled promise rejections. Instead of logging a warning, it throws an error and exits the process. This change encourages developers to handle promises properly.

// This will throw an error and exit the process in Node.js 17
new Promise((resolve, reject) => {
  reject(new Error('Unhandled Rejection!'))
})

4. QUIC protocol (experimental)

Node.js 17 introduced an experimental implementation of the QUIC protocol, aiming to provide a more efficient and secure transport than its predecessors. While still in its experimental stage, developers can play around with it and provide feedback.

Deprecations and Removals

As with most new versions, it’s essential to note that some features and APIs might be deprecated or removed. Before migrating, always consult the official Node.js documentation to ensure your codebase’s compatibility.

Conclusion

The continuous evolution of Node.js showcases its commitment to address developers’ needs for performance, compatibility, and security. With the release of Node.js 16 and 17, significant upgrades, like the V8 JavaScript Engine improvements and the introduction of OpenSSL 3.0, have been introduced. Moreover, the emphasis on safer defaults, as evident from the change in handling unhandled promise rejections, underlines the drive towards crafting a more robust and error-free environment for developers. Additionally, the experimental introduction of the QUIC protocol indicates Node.js’s forward-looking approach, staying abreast with emerging technologies. As always, while enjoying the new features and improvements, developers must remain vigilant about deprecated features and consult official documentation when considering migration.