Mepo is focused on hackability and performance. It enables endless expandability through its mepolang.
Mepo just reached milestone 5 (tag 0.5) with major performance and usability improvements, including savestates from session to session.
Check it out! or even better: contribute by your user feedback, patches and such!
probably through mepolang scripts already, although right now in the interface i don’t know. it’s a very good question…