SIP 26 - Featherproof

Background Stargate currently uses MPT (merkle patricia trie) (https://github.com/LayerZero-Labs/LayerZero/blob/main/contracts/proof/MPTValidator01.so) in its LayerZero configuration as a validation library. This directly impacts gas cost paid to the relayer by Stargate and the end user sending a transaction.

Stargate currently uses the newest ULNv2 validation library (https://github.com/LayerZero-Labs/LayerZero/blob/main/contracts/UltraLightNodeV2.sol) that launched on September 5, 2022. This has been in production for over 4 months and has seen $2,203,933,589.46 volume pass through Stargate along with 1,501,174 messages over LayerZero. During the time Stargate has been using this LayerZero released a new validation library called Featherproof (https://github.com/LayerZero-Labs/LayerZero/blob/main/contracts/proof/FPValidator.sol) which is actively used when interacting with Aptos. Featherpoof has been used in production for 4 months, has seen 185,448 messages go across it. Featherproof secures large applications like CAKE, BTC.b, and TheAptosBridge and offers a drastic reduction in gas – reducing gas costs by over 20%. Gas costs have commonly and repeatedly been brought up as one of the largest limiting factors of the current Stargate implementation, this would be a massive improvement in that.

Proposal Stargate should adopt Featherproof. This would result in a bare minimum cost of 20% less gas in all transactions and in certain edge cases (such as aggregators) can result in more than 90% less gas cost. A more consistent and significantly cheaper gas cost will make Stargate more usable, more frequently utilized within all third party routing, and offer a significantly better user experience to all.

Execution A configuration change to the relayer Stargate uses would need to happen for this to be enabled. Stargate will need to select Featherproof as it’s validation library rather than ULNv2. This can be done near immediately after this proposal passes.

Success If successful, Stargate’s gas usage will decrease by at least 20%. This will give Stargate an edge in an a bridge landscape that is growing more competitive over time. It will also improve user experience when interacting with Stargate by lowering the amount paid by the user.

Upon success, Stargate will become significantly more competitive in the overall landscape for gas pricing and will reduce gas usage of at least 20%. Reducing gas cost will also improve user experience, rate of inclusion in aggregators, and generally reduce friction on the end user by a meaningful amount

Summary Stargate will migrate to the more gas efficient validation library Featherproof for all cross-chain transactions resulting in a significantly decreased cost to the end user and a more competitive Stargate experience.