Promises are in ES6. There is a prototype version of them in V8 behind the usual --harmony flag, although it is very bad and deviates from the standard quite a lot. E.g. it passes 221/879 of the Promises/A+ tests [1], which only test the then method; it also deviates on other methods, as noted in the article [2].

Node tends to keep up with V8 versions pretty well, so I anticipate by the time Node 0.12 is released the --harmony flag will enable the Promise global. (Hopefully by then the V8 team will have gotten their act together on standards compliance.) Node core though is pretty committed to the error-first callback pattern; that will be a longer shift, I think.

[1]: https://twitter.com/promisesaplus/status/407721467778846720 [2]: http://www.html5rocks.com/en/tutorials/es6/promises/#toc-api