Node.js 8: Big Improvements for the Debugging and Native Module Ecosystem

Node.js Collection
Published in
4 min readMay 31, 2017


We are excited to announce Node.js 8.0.0 today. The new improvements and features of this release create the best workflow for Node.js developers to date. Highlighted updates and features include adding Node.js API for native module developers, async_hooks, JS bindings for the inspector, zero-filling Buffers, util.promisify and more.

Throwing confetti now that we have Node.js 8!

The Node.js 8 release, replaces version 7 in our current release line. The Node.js release line will become a Node.js Long Term Support (LTS) release in October 2017 (more details on LTS strategy here). The LTS release line is focused on stability and security and is best for those who want guaranteed stability when they upgrade and/or are using Node.js in the enterprise.

Those who need stability and have complex production environments (i.e. medium and large enterprises) should wait until Node.js 8 goes into LTS before upgrading it for production.

Now that we’ve provided this PSA, let’s dive into the interesting updates in this release.

Native Modular Ecosystem Gets a Boost

The much awaited Node.js API (N-API) will be added as an experimental feature to this release — it will be behind a flag. This is an incredibly important technology as it will eliminate breakage that happens between major releases lines with native modules.

Although native modules (modules written in C or C++ and directly bound to the Chrome V8) are a small portion of the massive modular ecosystem, 30 percent of all modules rely indirectly on native modules. Every time Node.js has a major release update, package maintainers have to update these dependencies.

These efforts would not be possible without significant contributions from Google, IBM, Intel, Microsoft, nearForm, NodeSource and individual contributors. Read the full details around these efforts and this technology here.

Anyone who builds or uses native modules should test out the N-API feature.

Welcome, V8 5.8

Node.js 8 ships with V8 5.8, a significant update to the JavaScript runtime that includes major improvements in performance and developer facing APIs. V8 5.8 is guaranteed to have forwards ABI compatibility with V8 5.9 and the upcoming V8 6.0, which will help ensure stability of the Node.js native addon ecosystem. During Node.js 8’s lifetime, the Node.js Project plans to move to 5.9 and possibly 6.0.

The V8 5.8 engine also helps set up a pending transition to the new Turbofan and Ignition compiler pipeline, which leads to lower memory consumption and faster startup across Node.js applications. Although this has existed in previous versions of V8, TurboFan and Ignition will be enabled by default for the first time in V8 5.9. The new compiler pipeline represents such a significant change that the Node.js Core Technical Committee (CTC) chose to postpone the Node.js 8 release in order to better accommodate it.

Buffer Improvements

The zero-filling Buffer (num) and a new Buffer (num) are added by default. The benefit of the zero-filling Buffer helps with security and privacy to prevent information leaks. However, the downside with this buffer is that folks using it will take performance hits, but this can be avoided by migrating to buffer.allocUnsafe(). It is suggested that Node.js users only use this function, if they are aware of the risks and know how to avoid those problems.

WHATWG URL Parser is Now Stable

WHATWG URL parser goes from experimental status to fully supported in this version, allowing people to use a URL parser that is compliant to the spec and more compatible with the browser. This new URL implementation matches the URL implementation and API available in modern web browsers like Chrome, Firefox, Edge and Safari, allowing code using URLs to be shared across environments.

Performance, Security and Interface Boost in npm@5

Npm, Inc. recently announced the release of version 5.0.0 of the npm client and we are happy to include this new version within Node.js 8.

Common package management tasks such as package installation and version updates are now up to five times faster; lockfiles ensure consistent installations across development environments; and a self-healing cache with automatic error recovery protects against corrupted downloads. npm@5 also introduces SHA-512 code verification.

“Since npm first shipped with Node.js in 2011, our mission has been to reduce friction for Node.js developers and help people build amazing things. Using Node.js 8 with npm@5 will make modular software development dramatically faster and easier — it’s the largest performance improvement ever,” said Isaac Z. Schlueter, CEO of npm, Inc. “We’re proud of our commitment to the Node.js community, and collaboration to bring innovative products to market. I’m excited to see what comes next.”

Insights to the Tooling Ecosystem and Debugging

This release line will provide deep insight via the new tracing and async tracking features. The experimental ‘async_hooks’ module (formerly ‘async_wrap’) received a major update in Node.js 8. This diagnostics API allows developers to monitor the operation of the Node.js event loop, tracking asynchronous request and handles through their complete lifecycle and enabling better diagnostic tools and other utilities.

These additions, along with the removal of the legacy debugger (which is replaced by the newer CLI debugger that landed in v7) make it easier to debug and track changes within Node.js, allowing commercial and open source tooling vendors to pinpoint performance degradation in Node.js applications.

Another experimental feature added to this release includes JS bindings for the inspector. The new inspector core module enables developers to leverage the debug protocol used by the Chrome inspector in order to inspect currently running JavaScript code.

Improved Support for Promises

Node.js includes a new util.promisify() API that allows developers to wrap callback APIs to return Promises with little overhead, using a standard API.

For all of our major updates, please go to our technical blog and read more here.



Node.js Collection

Node.js is a collaborative open source project dedicated to building and supporting the Node.js platform.