As of Feb 20, 2018, the developers of Parsoid are deprecating support for node v4. Parsoid is the service that powers VisualEditor, Content Translation, Structured Discussions (formerly Flow), and other MediaWiki features. If you don't run a MediaWiki install that uses VisualEditor or these other features, then this announcement does not affect you.
Node v4 is reaching end of life (EOL) on April 30, 2018 [1].
In March, we'll release our next debian [2] and npm [3] packages. This will be the last release that will have node v4 support. We'll continue to provide any necessary critical bug fixes and security fixes for these packages till node v4's EOL date.
If you are running a Parsoid service on your wiki and are still using node v4, please upgrade your node version by May 2018. Parsoid has been tested with node v4, v6 , v8 and the latest (v10) and works with all these versions. So, the upgrade away from node v4 should be seamless from the Parsoid point of view.
The Wikimedia cluster runs node v6 right now and will be upgraded to node v8 some time this year. However, we are dropping support for node v4 right away from the master branch of Parsoid. Going forward, the Parsoid codebase will adopt features available in node v6 and higher (async / await) which aren't supported in node 4x and will constitute a breaking change.
Going forward, we will NOT be issuing these node version deprecation announcements. Parsoid's support for specific node versions will be dropped around the same time that the specific node version reaches its EOL.
Subbu, On behalf of the Parsoid developers.
[1] Node.js Long Term Support schedule @ https://github.com/nodejs/LTS [2] https://www.mediawiki.org/wiki/Parsoid/Releases https://www.mediawiki.org/wiki/Parsoid/Releases [3] https://www.npmjs.com/package/parsoid https://www.npmjs.com/package/parsoid