Withdrawals must normally wait
finalizationDelay Ethereum blocks until the rollup block they are included in is finalized, at which point the funds can be withdrawn. As the finalization delay is supposed to be set quite long to be robust against censorship attacks and short-term chain congestion, this leads to poor UX. We can do better!
Liquidity providers can offer up liquidity to users wanting to withdraw quickly, in exchange for a fee. Unlike lending protocols that are popular in DeFi, liquidity providers for fast withdrawals have zero systemic risk if they fully validate Fuel blocks before accepting a swap, as valid blocks are guaranteed to finalize and they can always catch invalid blocks.