¶ Overview
BOB (Build on Bitcoin) is a hybrid Layer 2 chain that combines Bitcoin security with the programmability of Ethereum. BOB has initially deployed as an OP stack rollup on Ethereum, which gives native support to ERC-20 tokens, access to DeFi liquidity, and easy on- and off-ramps with major exchanges. Sovryn has deployed its dapp on BOB, making Sovryn a multi-chain dapp.
¶ Features
EVM smart contracts: BOB runs the Ethereum Virtual Machine (EVM) as an Ethereum rollup. This gives BOB developers access to all the tooling, wallets, analytics, and other infrastructure that has been developed around Ethereum.
Bitcoin alignment: BOB is oriented toward bitcoin and bitcoiners. The goal is to incorporate the security of bitcoin PoW as well as to contribute to the bitcoin economy by opening new opportunities and use cases for bitcoin without waiting for an elusive hard fork of bitcoin.
Dual liquidity: Because BOB has bridges with both Ethereum and bitcoin, it can tap into the liquidity of both of these ecosystems as well as allow interaction between them. Developers and projects from either ecosystem will find an attractive opportunity to draw liquidity from the other ecosystem.
¶ Get on BOB
Users can interface with BOB in multiple ways.
Sovryn on BOB currently allows users to swap assets on the Sovryn DEX, provide AMM liquidity, and stake SOV. The Sovryn dapp gives direct access both to BOB and Rootstock.
To use BOB, users must bridge in assets from Ethereum using the BOB bridge. ETH must be bridged in for gas. Keep in mind that gas fees are dramatically lower on BOB than on Ethereum due to the use of rollup technology.
¶ Deposit to BOB
¶ 1. Visit the BOB bridge
- Go to the BOB bridge and Connect Wallet.
¶ 2. Select Deposit and chain
- By default, Deposit will be selected. If it isn't selected, click on Deposit.
- Select the chain from which funds will be sent to BOB. Note: If you select a sending chain other than Ethereum, the 3rd Party option will be activated and will present a selection of 3rd-party bridges available for the selected chain. These bridges are not covered in this step-by-step guide; see the documentation for the individual 3rd-party bridges for more details.
¶ 3. Specify amount and asset
- Specify the asset and the amount of that asset you want to bridge. Currently, the tokens available for bridging are: ETH, ALEX, DAI, USDT, WBTC, rETH, tBTC, eSOV, STONE, DLLR, USDC, and wstETH.
¶ 4. Bridge and confirm
- Click the Bridge Asset button and confirm the transaction in the dapp and your wallet.
- Note that the bridge time for deposits is approximately 3 minutes. However, bridge time for withdrawals is approximately 7 days due to the way rollups work.
¶ Withdraw from BOB
¶ 1. Visit the BOB bridge
- Go to the BOB bridge and Connect Wallet.
¶ 2. Select Withdraw and chain
- Click on Withdraw.
- Select the chain to which funds will be sent from BOB. Note: If you select a receiving chain other than Ethereum, the 3rd Party option will be activated and will present a selection of 3rd-party bridges available for the selected chain. These bridges are not covered in this step-by-step guide; see the documentation for the individual 3rd-party bridges for more details.
¶ 3. Specify amount and asset
- Specify the asset and the amount of that asset you want to bridge. Currently, the tokens available for bridging are: ETH, ALEX, DAI, USDT, WBTC, rETH, tBTC, eSOV, STONE, DLLR, USDC, and wstETH.
¶ 4. Bridge and confirm
- Click the Bridge Asset button and confirm the transaction in the dapp and your wallet.
- Note that the bridge time for withdrawals is approximately 7 days due to the way rollups work.
¶ Roadmap
The BOB roadmap consists of four stages:
Phase 1 (Complete)
BOB has been bootstrapped as an optimistic Ethereum rollup.
Phase 2 (In progress)
The Ethereum rollup will be extended to include bitcoin PoW Security.
Phase 3 (In research)
BOB will be converted to an optimistic bitcoin rollup that uses BitVM.
Phase 4 (In research)
BOB will be converted to a ZK-rollup if bitcoin adds the necessary opcode to enable ZK-rollups.