The Node.js Foundation has released version 7 of the platform, including version 5.4 of the V8 JavaScipt Engine.
James Snell, member of the Node.js core team, said that the release brings 98% coverage of ES6 language features, along with improved reliability and performance. V7 also uses the new experimental URL parser based on the WHATWG URL standard, making parsing the same in Node.js as it is on the browser, as well as bringing improved HTTP 1.1 spec compliance for better input validation and enhanced security, and future support for HTTP/2.
Myles Borins, a member of the Node.js project Core Technical & Collaborators Committee, told InfoQ:
Node.js is working on how best to respond and adapt to new language features to ensure that the Node.js environment will serve our users needs. This is not an easy task. Key features under discussion include: Promises (making Promises compatible with Node.js debugging and making the Node.js API compatible with Promises), async await, and supporting the ES6 Module specification.
During this process, members of the Node.js project are working with the TC-39 to ensure that new JavaScript language features meet the needs of Node.js users.
In the blog post V8 Release 5.4 Google engineer Michael Hablich says the performance improvements in the 5.4 release are related to key improvements in memory footprint and startup speed.
"Memory management inside V8’s JavaScript parser was simplified to avoid unnecessary allocations, reducing off-heap peak memory usage by up to 20%. This memory savings is especially helpful in reducing memory usage of large script files, including asm.js applications," Hablich said.
Also updated in V8's APIs is the ability to create a v8::Function directly without a prototype, and providing a convenience array buffer allocator.
Because Node.js v7 ships with V8 5.4, it is noted that existing native addons will need to be recompiled to avoid runtime errors when trying to load them. Developers should use npm rebuild or simply remove node_modules and npm install from scratch.
V7 is a checkpoint release for Node, and so the impacts of it are less far-reaching than LTS releases. Chairperson for the Node.js TSC Rod Vagg, said the key focus for v7 was "to make sure modules in the ecosystem are keeping up with Node Core."
With Node.js v8 scheduled for release in April 2017, v7 will only be supported until June of that year, with v6 continuing under Active LTS and Maintenance until 2019.
Developers who need stability and have a complex production environment are encouraged to stay on v6, while those with the ability to upgrade versions quickly and easily without disrupting their environment are welcome to upgrade to v7.