Node v4.0.0 (Stable) | Node.js
2015-09-08
"Node.js project and the io.js project that are now combined in a single codebase
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Node.js v4.0.0 contains V8 v4.5, the same version of V8 shipping with the Chrome web browser today. This brings with it many bonuses for Node.js users, most notably a raft of new ES6 features that are enabled by default including block scoping, classes, typed arrays (Node's Buffer is now backed by Uint8Array), generators, Promises, Symbols, template strings, collections (Map, Set, etc.) and, new to V8 v4.5, arrow functions."