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Understand the value of 1 million to 10 million US dollars!

1. BTC Layer 2 Dispute and RGB++

If you want to explain UTXO Stack clearly, you can’t avoid RGB++.

There are more than 20 BTC Layer 2 solutions on the market, but most of them are EVM solutions, which basically use ETH's technology stack + bridge to solve BTC's expansion problem. Although the ecosystem can be quickly built in the short term, in the long run, this solution has no strong binding relationship with the BTC main chain in terms of security and is heavily dependent on the bridge. Secondly, ideologically, using ETH's Account model and EVM virtual machine to expand BTC UTXO is somewhat not "Bitcoin Native".

The Lightning Network has been running for many years but has not achieved the desired results, and has a natural expansion shortcoming of not being able to support smart contracts. Solutions based on client verification paradigms such as Taproot and RGB also have many problems such as long implementation time and slow technological progress. This is also the main reason why the current EVM expansion solution is popular.

Nervos CKB, which has been deeply involved in the public chain field for many years, has used the natural structural advantages of PoW+UTXO like BTC + innovative "isomorphic mapping" technology to "seamlessly migrate" RGB's client verification paradigm to CKB, named RGB++. It sacrifices a little privacy in exchange for great functional and flexibility expansion, and its security is strongly bound to BTC L1. More importantly, RGB++ was announced to be truly launched at the Hong Kong Carnival in the past few days! This means that this is no longer a capacity expansion narrative that remains at the conceptual or development level, but a product that can actually start to build an ecosystem and solutions.

If the above terms like client verification and isomorphic binding are still too abstract, then RGB++ can be understood by the following approximate analogy: a user initiates a transaction on BTC L1 to trigger the RGB++ asset transaction belonging to the user on CKB. When the transaction is completed on CKB, it is written back to a Commitment on BTC L1.

Everyone may wonder: this doesn’t save gas fees, right? Users still have to initiate transactions on BTC L1 and still have to pay BTC gas fees. Now they have to add CKB gas fees, which makes it more expensive?

In fact, there are four benefits:

1. As an asset issuance protocol, RGB++ enables BTC L1 to issue new RGB assets (think Merlin's BRC420).

2. RGB++ asset transactions on CKB are fully Turing complete and programmable.

3. After multiple RGB++ transfers are completed, you can aggregate and send a Commitment to Bitcoin L1. This is called "transaction folding". It looks very similar to Rollup, which saves a lot of gas fees.

4. Not only RGB++ assets can be mapped to CKB, but also Atomicals, Runes and other assets with UTXO characteristics can be mapped to CKB for Turing-complete transactions.

Because only UTXO on Bitcoin L1 can operate or update RGB++ UTXO, in RGB++, CKB becomes the "execution + DA" layer of BTC, and BTC L1 becomes the true "settlement layer", which is currently impossible for any EVM or non-EVM BTC expansion plan to do.

What if you think this solution is not fast enough and the cost is not low enough? After all, transactions on BTC L1 are still inevitable, and the maximum TPS of CKB as a PoW L1 ​​is only a few hundred. Is there a more flexible and fast expansion solution, like... Appchain in the ETH ecosystem?

So we have UTXO Stack, the “OP Stack” based on BTC and RGB++.

二、UTXO Stack: BTC 的 OP Stack + EigenLayer

If you are familiar with OP Stack and RAAS (Rollup as a Service) protocol stack, UTXO should be very easy for you to understand.

With UTXO Stack, you can issue BTC-like UTXO Appchains with one click, and these Appchains have the following features:

1. UTXO model, ultra-high TPS (UTXO inherently comes with parallel processing), and ultra-low Gas fees.

2. PoS mechanism, security is provided by BTC/CKB staked on BTC (similar to EigenLayer).

3. The asset protocol adopts RGB++. Due to the existence of isomorphic mapping technology, assets can be transferred arbitrarily between Appchain/CKB/BTC without the need for a cross-chain bridge.

4. The CKB smart contract stack can be reused.

5. BTC wallet can be reused (users are unaware of the CKB chain).

Finally, we have a Bitcoin-native, UTXO-based one-click chain launch infrastructure. This infrastructure also integrates the Restaking concept proposed by EigenLayer, which not only empowers BTC and CKB better, but also ensures the cold start and security of Appchain.

It is foreseeable that in the near future, BTC EVM Layer 2 and BTC UTXO Layer 2 will engage in a head-on confrontation at multiple levels, including technology, ecology, and even ideology.

It took less than two months from the official proposal of RGB++ in February to its implementation in April, demonstrating the team's extremely strong engineering capabilities. UTXO Stack was launched at the same time as RGB++, giving BTC ecosystem assets more diverse issuance and gameplay + Bitcoin Native possibilities. We believe and work with UTXO Stack to push the Bitcoin ecosystem towards a better and more prosperous future.

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