Well, again, most of the dependencies we used in Ruby did not see any update in the 3 years we've been using them. We also reported several bugs in those libraries/dependencies which were never fixed. This led us overtime to use our own branch of all the significant dependencies we had (including the MySQL gem for EM, the redis gem... and several other key ones).

Most of node modules are still in active development. As I've stated in the blog post, that's a pro and con, but we estimated that the pro was greater than the con :)