Bridge

Hyperliquid runs with an EVM bridge that is secured by the same validator set as the Hyperliquid L1.

Deposits to the bridge are signed by validators on the L1 and are credited when more than 2/3 of the staking power has signed the deposit.

Withdrawals from the L1 are immediately escrowed on the L1, and validators sign the withdrawal as separate L1 transactions. When 2/3 of the staking power has signed the L1 withdrawal, an EVM transaction can be sent to the bridge to request the withdrawal.

After a withdrawal is requested, there is a dispute period during which the bridge can be locked for a malicious withdrawal that does not match the L1. Cold wallet signatures of 2/3 of the stake-weighted validator set are required to unlock the bridge.

After the dispute period, finalization transactions are sent, which distribute the USDC to the corresponding destination addresses.

There is a similar mechanism to maintain the set of active validators and their corresponding stake on the bridge contract.

Withdrawals do not require any Arbitrum ETH from the user. Instead, a withdrawal fee of 1 USDC is paid by the user on the L1 to cover the Arbitrum gas costs of the validators.

The bridge and its logic in relation to the L1 staking have been audited by Zellic. See the Hyperliquid github repository for the full bridge code, and the Audits section for the audit reports.