In winter 2022 I reworked our 2019-2022 work-in-progress materials on RISC-V Composable Custom Extensions into the Draft Proposed RISC-V Composable Custom Extensions Specification .
We presented a poster (narration) on this work at the 2022 Paris RISC-V Summit. Then we stepped back, to work elsewhere, and waited to see if there were new interest or uptake in the work. Some but no groundswell!
I did some development work towards that first still-pending end-to-end composition demo. I added some example CFUs to the nascent CFU Zoo , including implementations of the three CFU-LI level adapters and a CFU Switch.