Stacks’ Mitchell Cuevas talks building integrated DeFi bridges for Bitcoin users

The Stacks ecosystem is a collection of independent entities, developers and community members working to build a user-owned internet on the Bitcoin (BTC) blockchain. Stacks’ STX cryptocurrency was distributed to the general public through the first-ever Securities and Exchange Commission-qualified token offering in the United States.

Mitchell Cuevas, head of growth for the Stacks Foundation, held an exclusive ask-me-anything, or AMA, session with Cointelegraph Markets Pro users on Dec. 2. During the session, he discussed the Stacks blockchain’s technological capabilities, future growth and major developments.

Cointelegraph Markets Pro User: PoW [proof-of-work] blockchains are known to be the most secure. Does Stacks PoX [proof-of-transfer] match BTC security or are there other vulnerabilities?

Mitchell Cuevas: Stacks’ consensus recycles PoW already done to secure Bitcoin. It does this via Proof of Transfer, a mining mechanism that provides a new take on consensus, allowing for a Proof of Work chain to be leveraged and extended in new ways. As a result, all Stacks transactions settle on Bitcoin, enabling Stacks transactions to benefit from Bitcoin’s security. Every Bitcoin block, Stacks transactions are batched and hashed on the Bitcoin blockchain. In addition, the history of all Stacks blocks produced is recorded to Bitcoin.

CT Markets Pro User: With smart contract capabilities, how long before Stacks will be able to integrate NFTs, gaming, and metaverse experiences?

MC: This can already be done and is being done today. We see massive growth of NFTs, reaching about $6-7 million in daily transacted value of late. The cost varies based on network activity. The minting cost is generally somewhere from $0.15 to $0.50. NFTs can be minted on Boom at boom.money. Monday games are building an exciting metaverse style open-world game. We’ve got teams, such as Jolocom, working on various identity-related efforts, which will be important in the metaverse. It’s exciting because the idea of the metaverse was an early anchor point for folks working at Blockstack back in the day, it was our company book, and we had Neal Stephenson out to one of our summits!

CT Markets Pro User: I only know of a few other platforms that build off of BTC to maximize its security, decentralization, and popularity (Lightning, RSK, Sovryn). So why do you think there aren’t more protocols integrating with BTC?

MC: It’s the difficulty of it. It took core engineers and the Blockstack team a while to crack Proof of Transfer, making the fully expressive contract layer possible in a truly decentralized way. When you have the option of working with a restrictive and unmoving base like Bitcoin or something else (or creating your chain entirely), I think many will end up in that last bucket. It’s an easier path and with how hot crypto is, is I can assume it’s more immediately lucrative, so that’s where the focus has stayed.

CT Markets Pro User: There were congestion issues with Stacks. Has that been resolved?

MC: For the most part — the main bottleneck that was noticed was the popularity of some NFTs and the architecture of the stacks-blockchain-API. Since then, the architecture has changed a bit, so many read-only API nodes can be brought up during higher traffic events, as we noticed in the past. The API write node is still a 1:1 ratio to a Stacks node running in follower mode since any particular blockchain node can be slightly ahead/behind other nodes at any given moment, making load balancing very difficult. In addition, an upgrade to the chain is expected to go live around December 8th that will provide a 2-10x increase in capacity. There are additional exciting future scalability and speed solutions now being explored that should give developers several different options as they build.

CT Markets Pro User: Can you explain microblocks? Is that the main factor to allow Stacks to scale?

MC: This is a great question and one we’ve seen some confusion about in the past. However, it is essential to note that microblocks are NOT a scalability solution; they allow faster transaction confirmations. To put it simply, microblocks are intended to solve transaction latency, allowing transactions to confirm in seconds on the Stacks chain before they are later settled to Bitcoin.

CT Markets Pro User: PoW blockchains have gotten labeled as substantial energy consumers thanks to one guy who will remain nameless. Where does Stacks PoX rate for energy consumption? Since it integrates with BTC, have you had to explain this difference?

MC: As for Stacks, it’s a straightforward narrative: PoX recycles PoW already spent on Bitcoin. This means we’re not burning or consuming new electricity for Stacks transactions. On a more personal note, I’ve been starting to work with some NFT artists that are passionate about making sure their environmental impact is zero or minimal, and they’ve been excited about Stacks. An early launch on Stacks included Cara Delevingne, and this was a vital issue for her as her NFT was going to benefit climate-related topics.

CT Markets Pro User: Each STX block is somehow recorded on the BTC blockchain. How much block space does this take? What is recorded?

MC: You can check this publicly! All of the BTC transactions are showing a size of 352 Bytes. The system’s state settles on Bitcoin — creating a new Stacks block entails sending a well-formed Bitcoin transaction that records the hash of a Stacks block and where it attaches to the blockchain. Settling the system on Bitcoin grants Stacks novel security properties not seen in other blockchains — it leverages the security of Bitcoin to guarantee that all Stacks forks are public and to help to bootstrap Stacks nodes identify the canonical Stacks fork and find Stacks blocks they have not yet downloaded.

CT Markets Pro User: How many full nodes are in operation? Is there a limit to the amount of decentralization that can be achieved?

MC: Short answer, there were a few hundred last we checked. For the rest, great question, and buckle up for a longer answer. It’s important to note that unlike PoW based networks, like Bitcoin, the number of STX miners alone is not an accurate reflection of a miner’s relative ability to win blocks over time. As a result, it does not reflect the security or decentralization of the network. To successfully attack Stacks 2.0, a miner would need to mine a genuinely longer chain than the rest of the network. Unlike a PoW based chain, the Stacks chain quality is measured by its length and not the total amount of BTC burned (or resources expended). This means that simply spending 100x the BTC of every other miner will not result in a longer or better Stacks chain tip. Instead, a miner would have to consistently out-mine every other participant to attack the Stacks chain successfully. To do this, a “bad actor” miner needs to effectively guarantee they could win every block over the period their attack occurs.

CT Markets Pro User: Any plans for interconnectivity with other blockchains? What solutions can be employed today?

MC: Yep! The community has several bridge efforts, including bridges to public blockchains such as Ethereum, BSC, SOL, Polygon, Klaytn, ICON, Orbit, etc. See some of the initiatives below: Stacks Bridge — cross-chain transfer service that allows owners of ETH or STX based NFTs to move their NFTs between blockchains; Banana Bridge — Megakongs will mint on Ethereum and be transferable back forth to Stacks, and this is an essential step. This opens them to Ethereum liquidity and, perhaps more importantly, it gives Bitcoin NFTs a gateway to access some of the exciting Metaverse projects vice versa; Orbit Chain — Orbit Chain is currently bridging Stacks and will soon welcome Bitcoin to the growing $100B+ DeFi Economy. Orbit Chain has built a notable reputation for itself in the past year, having bridged more than $10B worth of assets across other top chains, including Ethereum, BSC, Polygon, Klaytn, ICON, and Ripple.

CT Markets Pro User: Will the relevance of Layer-1/Layer-2 solutions on the BTC blockchain diminish over time should future updates like Taproot occur?

MC: Bitcoin is probably a stable blockchain precisely because it doesn’t change and is predictable. Any proposed changes can take a long time to merge since there is an incentive for the protocol not to change, and there is a large community with many opinions about any proposed change. Bitcoin is stable and predictable — so it’s unlikely that a native on-chain solution will supersede solutions like Stacks. Is it possible? Sure — but it’s also unlikely. Notably, Taproot doesn’t come close to bringing expressive smart contracts to Bitcoin.