We have spoken previously about combining the classic and indy jars for Groovy 3 (using a bit of simplification around the word "combining"). To date, we haven't done anything but some incomplete spikes for this task. I am suggesting we now target this work for Groovy 4. Adding further module support (Groovy 4) will no doubt require further indy bytecode and it might make sense to focus on that all together. Groovy 3 is usable in its current form, so pushing the indy re-work until later will let us bring out Groovy 3 sooner.