The node.js port is not yet up to feature-parity with the PHP original. But it works for simple text strings. Most of the missing features are simple changes and fixes.
I would prefer to re-work the library into a more proper functional style, as it suffers from some of the style of PHP, as it was a more-or-less direct port. If there is sufficient interest at the github page, and/or bitcoin-sponsored issues, I will devote time to fixing them. PR's are always welcome.