Bridges are critical infrastructure protocols that transfer tokens, arbitrary data, and smart contract execution calls between blockchain networks (e.g., Ethereum to Arbitrum or Solana). Canonical bridges act as the official native gateways designed by a specific network (e.g., Superbridge by Optimism) to lock assets on the primary chain and mint mirrored assets on the secondary chain. Cross-chain bridges operate independently, utilizing decentralized liquidity pools, off-chain relayers, or localized mint/burn mechanisms to facilitate instant third-party transfers.
Bridge Liquidity Transfer Fee Skim
Definition. Cross-chain bridges charge a standard protocol fee to users to facilitate instant transfers using pool reserves across networks. A micro percentage of this pool toll is programmatically routed to the CaaS rail before the remainder is distributed to the bridge’s liquidity providers or protocol treasury.
Value-stack tap. Execution Layer / Smart contract surface (bridge liquidity pool execution layer)
Cost-bearer class. Project paid / LP-borne, surplus (subsidized from the LP yield or protocol treasury margin, leaving the user’s bridge cost unchanged).
Example protocols. Stargate Finance, Synapse, Debridge
Relayer Gas-Abstraction Premium
Definition. Cross-chain transfers require independent, off-chain relayers to physically execute the transaction on the destination chain. These relayers charge a gas premium (buffer) upfront on the source chain to ensure they remain profitable despite destination-chain gas volatility. A fraction of this unspent execution surplus is captured by the CaaS rail during destination settlement.
Value-stack tap. Execution surface (relayer network / message passing layer).
Cost-bearer class. User paid (extracted from the unutilized gas safety buffer that the user already committed to paying).
Example protocols. LayerZero, Wormhole, Axelar.
Value flow.
Canonical Bridge Native Yield Drip
Definition. Canonical L2 bridges lock billions of dollars in L1 assets (like ETH or USDC) into a primary smart contract vault while issuing a mirrored asset on the L2. When these native L1 bridge contracts are upgraded to deploy this idle locked collateral into safe yield-bearing protocols, a percentage of this macro-yield is continuously streamed to the CaaS rail.
Value-stack tap. Smart contract surface (canonical L1 bridge vault contract).
Cost-bearer class. Project paid, surplus (derived from the macro treasury yield generated by the canonical bridging network).
Example protocols. Blast, Starknet (yield-bearing architectures), Polygon PoS Bridge.
Value flow.
Wrapped Asset Peg-Arbitrage Toll
Definition. When bridged derivative assets (like any-USDC or axlUSDC) momentarily lose their 1:1 peg with the native asset on a destination chain, arbitrageurs utilize localized bridge AMM pools to rebalance them. A dynamic micro-fee applied specifically during these high-volatility peg deviations is intercepted to fund the CaaS rail.
Value-stack tap. Smart contract surface (bridge specific AMM pools / localized swap router).
Cost-bearer class. User paid (extracted from arbitrageurs capturing localized cross-chain market inefficiencies).
Example protocols. Stargate, Superbridge