Ethereum

One important difference between shards and rollups that I did not get into is *upgradeability*: shards would upgrade their EVM automatically, rollups need their own governance. But could we change that? (thread)

I made one proposal a few months ago: https://notes.ethereum.org/@vbuterin/enshrined_zk_evm

Basically, do it in a highly flexible way by putting the proof system outside of consensus and letting individual clients prove in their own way. But the more I think about it, the more that seems overly complex and brittle.