The following sample works fine in node v5.1.0 but is broken in node v5.7.1:

path.normalize("/a/b/c/../../../x/y/z")

Correct (node v5.1.0): /x/y/z
Broken (node v5.7.1): /a/x/y/z

Note this works fine if the first path contains more than 1 character (e.g. "/aa/b/c/../../../x/y/z")