I spent some time diving deep into @build_on_bob, and this project has truly given me a new understanding of "the role of Bitcoin in DeFi." BOB is not just an ordinary Layer 2; it is a hybrid chain that combines the security of Bitcoin with the flexibility of Ethereum DeFi, with a clear goal—to allow BTC to truly participate in the world of DeFi, no longer just a "digital gold bar." For many years, Bitcoin has been the leader in the crypto world, but it is quite awkward that it has almost no presence in DeFi. Its TVL lags far behind Ethereum, and the reason is simple: the on-chain capabilities are too weak, and the cross-chain experience is poor. BOB aims to break this situation, transforming BTC from "lying there and increasing in value" to "being used and still earning." BOB's positioning is also very clear; it aims to turn BTC into an asset that can flexibly participate in DeFi. Whether you want to stake, borrow, or implement yield strategies, you can deploy it with one click, and the process is very smooth, making it quite friendly for beginners. I think this is particularly crucial because many BTC-related DeFi projects before were too engineer-focused, making it impossible for ordinary users to engage. Their tech stack is not simple either; it uses a ZK Rollup architecture running on Ethereum but employs a mechanism called BitVM to natively integrate Bitcoin, with security still backed by BTC. This is not just empty talk; BOB has not only participated in the design of BitVM2 but has also collaborated with many institutions to advance the testnet launch, indicating that they are not just building a bridge but are genuinely constructing one. What surprised me even more is their lineup of partners. Established projects like Uniswap, Aave, Euler, LiFi, and Chainlink have already joined, and institutions such as Fireblocks, Cobo, and ForDeFi are also supporting them. With the backing of stablecoins like USDC, USDT, and cross-chain components like Layerzero, the entire ecosystem is already taking shape. Additionally, they have put a lot of effort into user experience. Platforms like Staking Rewards, Xverse, and Everstake have integrated "one-click BTC DeFi," allowing you to easily start earning BTC rewards without the hassle of wallet juggling or cross-chain transfers, with an experience that is basically close to the smoothness of CEX. In summary, I believe BOB is currently the most reliable attempt to "truly involve BTC in DeFi." It is not about transforming Bitcoin but finding a more modern use for it. If you hold BTC and don’t want to just wait for its value to rise, then BOB is definitely worth a look. It can not only help you earn money but may also be a core piece of BTC in the new wave of DeFi. At the same time, keep an eye on the projects on @arbitrum!