io.js v3 is essentially a beta release of Node.js v4 with significant updates including many ES6 features
Paul Krill writes:
Compatible with npm, io.js was spawned as a fork of Node.js late last year after disagreements arose over Node’s direction. Everything was smoothed over this spring, and the two factions, which had many of the same participants, agreed to reunite. “The governance of io.js and Node.js have already converged, all that is left is the technical side, and io.js v3 is a significant step towards completing it,” said Mikeal Rogers, who has served as a spokesman for io.js, in an email.
“Developers need to know about io.js v3 because it’s a significant change to the native side of the platform they’ll need to understand in order to prepare for Node.js v4,” Rogers said. He also noted version 3.0.0’s status as the likely last release line for the platform.
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