After reading Ni Da's sharing, I carefully studied BOB @ build_on_bob again. I thought it was another shell with two layers, but I did see something different. I also compared it with Goal @ GOATRollup; BTCFi is now like the Ethereum ecosystem before the rise of OP and Arbitrarum, with many attempts but no widely accepted mainstream paradigm yet. After all, Bitcoin has such a large market value and many people hold it for so many years, but the on chain gameplay is almost empty. The L2 market of BTC has been watching which mode of BTCFi can run out; Various bridging solutions, either centralized hosting or an unparalleled experience. The progress of BTCFi has always been like pulling a big saw and grinding a big hammer. one ️⃣ BOB's approach can indeed serve as a new reference: It's not the kind of L2 declaration that says' we are the second layer of Bitcoin with high TPS', but rather: we don't chase TPS or aim for cheap GAS, we just want to safely and natively import BTC, and then like ETH, it can be staked, scheduled, and automatically run DeFi logic. To put it more bluntly: make Bitcoin no longer just "in an account", but become the underlying fund pool, trust foundation, and security anchor for all on chain behavior. two ️⃣ How did it do it? Three things make me feel that they have played quite well: BitVM+ZK Bridge: It is not a centralized bridge that relies on multiple signatures, but rather uses BitVM to verify cross chain behavior on the Bitcoin network, which is equivalent to communicating in the language of Bitcoin itself, greatly improving security. OP Stack+EVM compatibility: It means that you are writing an Ethereum smart contract, but BTC is behind it, not ETH. Babylon's BTC staking mechanism: capable of staking BTC, obtaining LST (liquid staking token), and then scheduling in DeFi scenarios. Once this thing matures, it may be the core component of BTCFi's true explosion. three ️⃣ Current issues: Of course, the problem is not small, and even a bit realistic: At present, there is only one verifier, the proposer of the whitelist; It has a somewhat centralized early beta flavor; The fault proof mechanism of OP Stack has not been launched yet, strictly speaking, it is not considered as "complete distrust"; The contract can be upgraded instantly with no user exit window, which is not a small issue for the secure Bitcoin ecosystem. But from another perspective, I think this is exactly what good projects look like in the early days: unlocking and dismantling mines while working, rather than just filling the world in the PPT. four ️⃣ Some data: BOB's TVL has now exceeded 70 million US dollars. I also took a special look and found that there are indeed a bunch of real users using it, not just data that has been flashed out. And these products are all quite interesting: BTC Vault, BOB Earn, and Hybrid Vault: with a focus on "giving BTC something to do". five ️⃣ Conclusion—— I recently researched Goal @ GOATRollup on the same track; Although GOAT and BOB are both working on BTCFi and Bitcoin Layer2, their technological paths, project visions, and development rhythms are completely different. GOAT follows the lightweight L2 route, emphasizing fast BTC interaction and EVM compatibility; Technically biased towards Layer 2 infraaggregator, aimed at bridging the interaction between BTC and ETH on multiple chains; More focused on the application layer, suitable for gaming NFT、 Liquidity applications Launchpad， Something that leans towards the user side. BOB is a hybrid BTC Layer 2, with the goal of creating an "Ethereum on Bitcoin" that combines the security of BTC with the programmability of ETH; More inclined towards the financial layer, suitable for self built DEX/Earn/vaults, focusing on BTC staking and lending; Overall, what does BOB feel like to me? It's like discovering an early Arbitrarum, but behind it is not ETH, it's BTC. Although there are still many places in BOB that have not been fully decentralized and tokens have not yet been launched, I sincerely believe that if this idea can work, BTC will no longer be just a "vault" for value storage, but a "means of production" that can participate in creating profits - then the entire DeFi ecosystem may be completely rewritten. If you have a long-term bullish view on BTCFi and lean towards a technical investment perspective, BOB is more worth lurking and following up on; But if you want to participate in more interactive activities and hope to ambush community projects that may quickly start, GOAT is more suitable for you to participate in the short and medium term. This track is still worth long-term research. What else can we pay attention to? Please add it!