Flame is an Astria-based EVM rollup that serves as TIA’s DeFi hub. The top of the block (ToB) in a DeFi-enabled rollup is particularly valuable because it provides an execution guarantee. As the amount of liquidity on Flame increases, the volume of MEV opportunities will grow, thereby increasing the value of Flame’s blockspace. With an increased demand for ToB execution, an auction is the efficient mechanism for allocating this privilege to a bidder, accumulating revenue for the Flame ecosystem.
rolluptobsequencingrule
Flame leverages Astria's lazy sequencer and sequencing rules to construct an auction for only the top-of-block bundle slot. As lazy sequencing separates inclusion from execution, Flame’s trusted Auctioneer simply needs to allocate, sign and include the auction-winning bundle in the sequencing-layer block. Flame’s execution enforces a sequencing rule that places the Auctioneer’s signed Allocation deterministically at the top of the block it was successfully included in. This provides bidders with a dedicated submission path that offers two key benefits:
Bidders submit their bundles directly to the trusted Auctioneer's node, keeping their traffic separate from regular (i.e. MetaMask) users who submit transactions via the rollup’s mempool. This contains congestions and prevents the adverse effects on regular users during periods of high market activity, such as spikes in gas costs.
The auctioneer runs a sealed-bid first-price auction that allocates the top-of-block slot to the highest bidder. This ensures that only the winning bidder's bundle is posted and only they pay for their transactions.Unlike priority fees, which charge all bidders regardless of winning, this system only charges the winning bidder.
Bids are sent by bidders directly to the Auctioneer’s node, and do not go through a public mempool. Bidders cannot see other submitted bids nor the corresponding payloads.