Information about the language of the implementations would be helpful

[Vampire]

If I'm for example searching a Java implementation that supports a specific extension, it would be nice to be able to find out or even filter for the language of an implementation if it is a library.

[fingolfin]

Yeah, filtering would be nice, see also #6 (but these days I have little time to work on this hobby, so somebody else will have to contribute this, I am afraid).

And adding the implementation language where known is of course also fine.

[Vampire]

Ah, ok, then #6 for the filtering and here for adding language. :-)