Using xpath may improve querySelector performance

[poef]

DomDocument has support for spatch selectors, which support most of the CSS selectors. By offloading the search to the builtin function, you should be able to get improve performance quite a bit here.

Take a look at an implementation here: https://github.com/Ariadne-CMS/arc-xml/blob/master/src/xml.php#L53

[ivopetkov]

Sounds really good! Thank you!