What replaced the files contained in *systems-being-operated*

Hello, I am hitting a bug when loading lisp-unit2 as it (still) depends on the depreciated variable *systems-being-operated* (I did submit a ticket <https://github.com/AccelerationNet/lisp-unit2/issues/10>, but it is as yet not addressed). So I am trying to fix it myself. The *system-being-operated* variable was replaced by the boolean *in-operate* in 7c3f979c <https://gitlab.common-lisp.net/asdf/asdf/commit/7c3f979c0db4ac5f224ca634ce9ec5cb9d7cdf28> . *systems-being-operated* was a hash with a list of systems or NIL, while *in-operate* is a boolean (T or NIL). Does some other variable contain the information that *systems-being-operated* held? Thank you, Mirko