Bitcoin is still a young project that’s bound for disruption. While the money layer is supposed to never change, the advancements in cryptography and peer to peer networking will only improve its efficiency. As of late 2023 and early 2024, the most talked about breakthroughs are BitVM, covenants (with an ongoing battle between OP_CTV and OP_CAT), sovereign Zero Knowledge (ZK) rollups, and pegged sidechains (as described by BIP 300).

When I met John Light in Argentina during Labitconf, I instantly knew that I wanted to interview him. He did a stage presentation about Zero Knowledge proofs in Bitcoin which I was fortunate enough to catch, and about an hour later he also approached me after my own presentation about Breaking FUD. We spoke briefly and exchanged contacts, hoping that we will one day figure out the right time to record something.

A couple of hours later, while John Light and I were buying food, we ran into Super Testnet and Alexei Zamyatin. Super Testnet is known for his contributions to Lightning, BitVM, inscriptions, as well as his ambitions to put together assembly code for whacky purposes like locking BTC in a game of Pokemon. On the other hand, Alexei Zamyatin is a recovering academic cryptographer who concerns himself with problems such as building trustless bridges and sidechains. He is also into Zero Knowledge profs, and heads the BoB (Build on Bitcoin) initiative.

As we were all talking in the food court of Labitconf, Sergio Demian Lerner also showed up and joined the conversation. This all led to roughly 30 minutes of intensive banter about everyone’s projects and aspiration. It was then that I realized that I love the chemistry between them and how they complete each other, so I pitched an impromptu interview. Sergio Demian Lerner left and said he would participate another day, but John Light, Super Testnet and Alexei Zamyatin gladly accepted to immortalize our spontaneous gathering in a recording.

So we walked to the corner of the food court, which was only one fence away from a busy intersection from Buenos Aires. Our attempt to record a podcast was threatened by airplanes, a party bus, and a bunch of loud engines – but nothing could deter us from carrying on with our conversation about the future of Bitcoin.

As you’re about to notice, everything about our talk is very forward-thinking and, to some extent, avant-garde. The guests are talking about new cryptographic breakthroughs that may improve Bitcoin in ways that our imagination can’t even conceive at the moment – but might as well never get used for this purpose, either due to a premature protocol ossification or else because something new and better comes along.

The conversation with John Light, Super Testnet and Alexei Zamyatin isn’t lengthy, but covers lots of topics: they speculate on what the next Bitcoin soft fork activation may be (and agree on OP_CTV), they debate about the nature of Zero Knowledge Proofs in Bitcoin, they suggest some use cases for BitVM while also opining on Drivechains, they bring up rollups, and also express their opinion on ordinal inscriptions. Bitcoin conservatives who never looked into these breakthroughs will most likely scratch their heads and scream blasphemy every minute or so, but there’s definitely a lot of technological merit to these proposals and they do have the potential to change the ways in which we use and understand Bitcoin.

One day, I hope I will also do individual interviews with all three of them. But for what it’s worth, this recording turned out to be both educational and entertaining. Especially thanks to Super Testnet’s sense of humor, Alexei’s willingness to play along, and John’s apparent focus on ignoring anything off topic. I can’t think of a better trio – and for this, I must also thank Rodolfo Andragnes and the rest of the Labitconf organizers from Argentina.

Season 15 of the Bitcoin Takeover podcast is sponsored by Wasabi Wallet, Cryptosteel, Satochip, and IVPN!

Listen to John Light, Super Testnet, and Alexei Zamyatin on Spotify, Apple Podcasts, YouTube & X!

For a more sovereign and private experience, I recommend that you use this free player. You get the exact same audio quality and features as on Spotify, but without any kind of big tech tracking. Not only that, but you can download the episodes on your device for offline listening.

Time stamps:

Zero Knowledge Proofs (00:00:48) Discussion about applying zero knowledge proofs to Bitcoin and their potential for scaling solutions.

Impossibility Proofs for Bitcoin Bridges (00:01:49) Alexei Zamyatin explains impossibility proofs for Bitcoin bridges and the challenges of building them without trust.

Bitcoin’s Next Soft Fork? (00:02:51) Discussion about the candidates for Bitcoin’s next soft fork, with an emphasis on CTV.

Importance of Proposed Changes (00:04:33) The importance of skepticism towards proposed changes and the need for ongoing improvements to Bitcoin.

Ossification and Bitcoin Improvement (00:12:16) Debate on the concept of ossification and the need for continuous improvement in Bitcoin.

BitVM and Its Applications (00:16:12) Explanation of BitVM and its significance, including its potential for gaming, bridges, and security improvements.

Use Cases for BitVM (00:18:09) Discussion of potential use cases for BitVM, including gaming, atomic swaps, and secure bridges.

Favorite Scaling Solution and Future Research (00:23:15) Opinions on existing scaling solutions for Bitcoin and the potential for emerging solutions based on current research.

John Light’s Views on Scaling Bitcoin (00:23:26) Various scaling solutions and their trade-offs, including lightning, state chains, and Validia chains.

Super Testnet’s Views on Scaling Bitcoin (00:27:13) Interest in join pools and their potential for scaling with more people and the challenges of developing them.

Alexei Zamyatin’s Views on Scaling Bitcoin (00:28:13) Interest in covenants, bridging Bitcoin to sidechains, and the challenges and potential of integrating smart contracts with Bitcoin.

Trustless Bridges (00:29:56) The need for trustless bridges between Bitcoin and sidechains, considering the security and adoption challenges.

John Light Explains Zero Knowledge Proofs (00:32:56) Explanation of zero knowledge proofs, their application in cryptocurrency, and potential for scaling and privacy improvements.

Super Testnet Explains How Bitcoin Did ZKP First (00:36:35) Discussion on Bitcoin’s implementation of zero knowledge proofs and the potential for more applications.

Alexei Zamyatin on Zero Knowledge Proofs (00:37:17) Challenges and potential of using zero knowledge proofs for rollups and sidechains, including the need for generic verifiers and long-term stability.

John Light’s Views on ZK (00:41:51) Debate about the implementation of zero knowledge proofs and the historical context of their adoption in cryptocurrencies.

Mimble Wimble in Bitcoin? (00:43:19) Question about the Mimble Wimble extension block and its absence in current conversations about Bitcoin scalability and privacy.

Increasing the Block Size with Extension Blocks? (00:44:33) Discussion on extension blocks, memo symbol protocol, and their potential as scalability and privacy solutions.

Improvements to Bitcoin Privacy (00:45:38) Discussion about ongoing improvements to privacy protocols in Bitcoin, including the state of the art and the need for cost-effective and user-friendly solutions.

Mimble Wimble Protocol (00:46:33) Critique of the Mimble Wimble protocol and its lack of support and scalability, with a comparison to shielded transactions.

Proposal for Privacy and Scalability (00:47:29) Reflection on the historical proposal for privacy and scalability in Bitcoin, along with the clash between Austrian economists and cypherpunks.

Bitcoin as Free Market Money (00:49:55) Personal journey to Bitcoin as a better alternative to fiat and gold, emphasizing the software’s potential to improve as free-market money.

Improving Bitcoin’s Qualities (00:51:44) Discussion on the need for Bitcoin improvements, including privacy, fungibility, and scalability, to make it more attractive and user-friendly.

Thoughts on Austrian Economics (00:54:11) Critique of the association of Austrian economics with the euro and a comparison to American economics, followed by a light-hearted comment about Salma Hayek.

Contact Information (00:55:40) Sharing of contact details for the speakers, including social media handles and websites, with a focus on privacy and encrypted messaging.

Closing Remarks (00:56:35) Final comments and instructions on how to follow the speakers, concluding the episode.

The Quest for Scalability: Zero Knowledge Proofs and Beyond

John Light, a seasoned Bitcoin developer, shed light on the intricacies of zero knowledge proofs. This cryptographic technique allows one party to prove to another that a statement is true without revealing any information beyond the validity of the statement itself. The implications for privacy and scalability in Bitcoin are profound, and John’s insights were nothing short of revelatory.

The Impossibility Proofs for Bitcoin Bridges

Alexei Zamyatin, an academic and developer, brought to the table his expertise on impossibility proofs for Bitcoin bridges. His work challenges the boundaries of what we thought was possible, pushing us to reconsider how Bitcoin can interoperate with other blockchains while maintaining its core principles of decentralization and security.

BitVM: A New Hope for Bitcoin’s Future

Super Testnet introduced us to the potential of BitVM. This emerging technology could revolutionize the way we think about Bitcoin’s capabilities, extending its use cases to gaming, secure bridges, and even more robust security frameworks.

The Delicate Balance of Ossification

The concept of ossification, the idea that Bitcoin’s protocol will eventually become so stable that it no longer evolves, sparked a lively debate. While some may see this as an end goal, our discussion highlighted the importance of continuous improvement and the dangers of becoming stagnant too early in the technology’s lifecycle.

A Pluralist Approach to Scaling

All three guests advocated for a pluralist approach to scaling, exploring multiple solutions to find the best fit for various use cases. The conversation touched on the trade-offs between security, privacy, and usability, and the exciting potential of integrating zero knowledge privacy features into payment channel networks like Lightning.

Join Pools and Covenants: The Path to Mass Adoption

The enthusiasm for join pools was palpable as Super Testnet discussed the concept of shared custody of a Bitcoin address. The scalability and potential enhancements with technologies like CTV could be game-changers for Bitcoin’s future.

Alexei Zamyatin brought an application perspective, emphasizing the role of solutions like covenants in enabling new applications and improving custody solutions. Trustless bridges between Bitcoin and sidechains were also highlighted as critical for mass adoption.

Advertisements: Enhancing Privacy and Security

Our episode also featured advertisements for Wasabi Wallet and Crypto Steel, two products at the forefront of Bitcoin privacy and security. Their commitment to safeguarding users’ assets and transactions aligns perfectly with the themes of our discussion.

The Future of Bitcoin Scaling

As we wrapped up our conversation, we revisited the potential of zero knowledge proofs and the Mimble Wimble extension block proposed by Andrew Poelstra. The scalability and privacy benefits are clear, but the path to integrating these technologies into Bitcoin remains complex and challenging.

Conclusion: A Network in Evolution

This episode was a testament to the dynamic nature of Bitcoin development. The insights from the guests underscored the critical need for ongoing innovation and the exciting possibilities that lie ahead. As we continue to explore and debate the best paths forward, one thing remains certain: the Bitcoin community’s relentless pursuit of a scalable, secure, and private financial future.

Stay tuned for more episodes where we’ll continue to dissect the technicalities and triumphs of Bitcoin development. Until next time, keep your private keys secure and your mind open to the endless possibilities of cryptography.