> Erlang is great but its ecosystem is tiny compared to Node's, and as a programming language it's at least as quirky as JavaScript.

I disagree with this; while the syntax is unusual for many, its semantics are extremely simple and clear. I don't think it has anything quite like:

* JavaScript having `null` and `undefined`. * JavaScript lacking have proper integers. * JavaScript strings being UTF-16, so things like "".length don't work. * Scoping of 'this'. * The unmanageable automatic typecast rules * Semicolon insertion. * JavaScript `with (x) {` (maybe a cheap shot since it's so uncommon, but we are talking about language design).

Main quirks I can think of for Erlang are when people trip up over "strings", <<"binaries">>, and iolists. But I'd love to hear where others run into proper semantic quirks.