Brollups: Bitcoin-native Rollup Design

"Brollup is a Bitcoin-native rollup design that works with a native Bitcoin peg and does not require any changes to the Bitcoin protocol. The peg is enforceable on-chain and can be unilaterally redeemed at any time. Brollups are in a category of their own, neither optimistic, ZKP, nor sovereign."

https://www.nobsbitcoin.com/brollups-bitcoin-native-rollup-design/