Hop
Hop is a protocol for sending tokens across rollups and their shared Layer-1 network in a quick and trustless manner.
- Documentation
- Auditors
- Please see our FAQ on experienced auditors
- Website
- Token: HOP
- Tags: Cross Chain
- TVL: $93M (Rank #52)
- TVL Ranking by Cross Chain: #2
- Blockchain: Ethereum, Arbitrum, Optimism, Polygon, xDai
- Chain TVL
- Ethereum: $58.99M
- Arbitrum: $13.34M
- Optimism: $12.79M
- Polygon: $6.22M
- xDai: $1.69M
- Code reviewed by several experienced auditors including Solidified and Trail of Bits
- Public team promotes accountability
- No documented protocol hacks since launch
- Core protocol launched in 2021; maturity over a year reduces technical risk as smart contracts are moderately battle-tested
- Top 10% by total value locked reduces risk
- Decentralized governance increases transparency
- At least one critical governance issue documented
- No concerns identified
- Locally verified bridge that uses liquidity networks on each chain to enable cross-chain swaps; this system typically uses a lock/unlock mechanism to ensure the safety of user funds
How Hop works
Hop is a rollup-centric bridging solution that allows digital assets to be transferred between Layer-1 and Layer-2 networks. It consists of a rollup-to-rollup general token bridge for Ethereum's L2 ecosystem that enables users to send tokens quickly and trustlessly between rollups. To achieve this, Hop uses hTokens and liquidity pools. hTokens are intermediary cross-network bridge assets that allow tokens to move quickly across chains. The user only uses the native tokens when using the Hop bridge and does not directly deal with hTokens. Hop leverages the automated market maker (AMM) concept to create liquidity pools consisting of the native token and hTokens. Using AMMs, Hop swaps between the hTokens and the native assets on each chain. Hop uses Bonders to facilitate near-instant transfers across rollups. Bonders run a verifier node on each Layer-2 network and possess the ability to verify transactions. Bonders front liquidity on the destination chains in exchange for a small fee when sending between Layer-2s and back to Layer-1. There is no Bonder fee when sending from Ethereum to Layer-2 chains. They are assured their liquidity will eventually return when the transfer settles on Layer-1. The upfront liquidity provided by Bonders is what allows Hop to quickly and cheaply transfer tokens across chains.
How Hop makes money
Hop charges two types of fees: the AMM swap fee and the Bonder fee. The AMM swap fee is paid to users who provide passive liquidity. The swap fee is 0.04% for each conversion between an hToken and a native token. For rollup transfers, there are two conversions so the total fee is 0.08%, while transfers back to Ethereum mainnet only have one conversion. The Bonder fee is taken for fronting the liquidity of a user transfer at the destination chain and for taking on risk. This fee varies per asset and route based on the transaction volume.
How you make money on Hop
You can make money by depositing native assets into liquidity pools to earn AMM swap fees for every conversion with hTokens.
