BOB, short for Build on Bitcoin, is a hybrid Layer 2 built on the OP Stack that settles to Ethereum while connecting Bitcoinliquidity. Its token is BOB.
BOB, short for Build on Bitcoin, launched its mainnet in May 2024 as a hybrid Layer 2 built on the OP Stack that settles to Ethereum and aims to connect Bitcoin liquidity with EVM applications. Here is how it works and what it is used for, not the price.
Total value locked (DeFi)
$9.5M
Value locked in DeFi protocols on BOB. Updated Jun 8, 2026. Source: DefiLlama.
BOB runs on the OP Stack as an optimistic rollup and settles transactions to Ethereum. In an optimistic rollup, transactions are assumed valid when posted and can be challenged during a dispute window before withdrawals finalize. BOB is part of the OP Superchain, the group of chains built on the OP Stack, and the project describes plans to add Bitcoin security features over time. Gas is paid in ETH.
Consensus: OP Stack optimistic rollup
BOB runs on the OP Stack as an optimistic rollup and settles transactions to Ethereum. In an optimistic rollup, transactions are assumed valid when posted and can be challenged during a dispute window before withdrawals finalize. BOB is part of the OP Superchain, the group of chains built on the OP Stack, and the project describes plans to add Bitcoin security features over time. Gas is paid in ETH.
Hybrid design
BOB describes itself as a hybrid Layer 2 that aims to combine access to Bitcoin liquidity with the EVM application environment used on Ethereum.
OP Stack and Superchain
BOB is built on the OP Stack and is part of the OP Superchain, the group of chains that share Optimism technology and settle to Ethereum.
Optimistic rollup
Transactions are posted to Ethereum and assumed valid unless challenged during a dispute window, after which withdrawals finalize.
ETH for gas
Users pay transaction fees in ETH. The BOB token is used for staking and governance rather than as the gas currency.
Ecosystem & usage
What BOB is used for.
The network hosts EVM applications that aim to bring Bitcoin liquidity into decentralized finance.
BOB stands for Build on Bitcoin. It is a hybrid Layer 2 that settles to Ethereum and aims to connect Bitcoin liquidity with EVM applications.
Is BOB a Layer 1 or Layer 2?
BOB is a Layer 2. It is built on the OP Stack as an optimistic rollup and settles transactions to Ethereum.
What token pays for gas on BOB?
Gas on BOB is paid in ETH. The BOB token, which launched in November 2025, is used for staking and governance.
When did BOB launch?
BOB launched its mainnet in May 2024. It later joined the OP Superchain in October 2024.
Can I hold BOB in Zypto App?
Not yet. BOB isn't in Zypto App at the moment. You can hold it in any self-custodial wallet, and you can ask us to add BOB using the "Request BOB" button above.
