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Equilibrium's Infra Bulletin #2: Rollups - The More The Merrier?
Equilibrium Labs builds the state-of-the-art of decentralised infrastructure. We are a global team of ~35 people who tackle challenges around security, privacy and scaling.
This newsletter allows us to share more about what we read, what excites us and what we think is relevant to the space. In addition, you will get a glimpse into the organisation and our culture.
Research, Articles and Industry News:
Rollups have been a hot topic lately and this post by Kelvin is part of the debate. Its main argument (following a controversial post by Jon) is that social consensus over rollups is not defined by the rollup bridge in a fundamental way. It contrasts with the prevailing view which is based on the fact that today, most assets on rollups are bridged. This gives rollup bridges outsized influence over social consensus, which for example is used to decide which fork is the “real” one.
However, as these systems become more mature, it’s likely that an increasing number of assets will be natively issued on the chain rather than bridged. For example, Circle recently announced that they would start issuing USDC natively on Arbitrum, rather than relying on bridging. A catastrophic hack or bug could create a scenario in which it is significantly more valuable to save the native assets even at the cost of losing bridged ones. Therefore, social consensus is not fundamentally defined by a rollup bridge, it’s just how things work today.
Key takeaway: While the biggest rollup bridges today do exert a large amount of control over the social consensus, this might not always be true. Even though the terminology and definitions can be fuzzy, ultimately we shouldn’t confuse the practical reality (what is) with the fundamental reality (what could be).
📚Zero-Knowledge Fraud Proofs (Layer N and RiscZero) - Recommended by Hannes:
Zero-Knowledge Fraud Proofs (ZKFP) provide an alternative way to verify fraud proofs in optimistic rollups, which could be easier and cheaper compared to current models that rely on replaying transactions on-chain. Another key constraint with both simple replay proofs and interactive proofs is that instructions must be able to be executed the same way on the base layer and on the rollup (i.e. both implementations need to use the same virtual machine to ensure that the behaviour matches).
Layer N is an optimistic rollup and RISC Zero’s zkVM is a general-purpose zero-knowledge virtual machine. Combining the two allows Layer N’s execution environment to be ported into zkVM to produce a zero-knowledge proof of correct execution. In the case of a dispute, the verifier sends the proof to Layer N’s smart contract on Ethereum, which then checks whether the proof is valid.
Layer N is not the only one looking into ZKFPs. Optimism recently released a request for proposal on how zero-knowledge technology could be leveraged for both fraud proofs (L1 ↔️ L2 communication) and improved messaging between different OP chains (L2 ↔️ L2 communication). In addition, Metis envisions hybrid rollups that use transaction categories, where each category could be configured to automatically decide whether its transactions should be validated via Optimistic or ZK rollups if the user chooses to.
Key takeaway: ZKFPs could make it easier and cheaper to verify fraud proofs in optimistic rollups. In addition, they would enable getting around the issue of the execution environment having to be equivalent on both the base chain and rollup, since only the proof has to be verifiable on the base chain.
Stackr SDK is a framework for building app-specific micro-rollups in web2 programming languages. Most existing rollups today are general purpose, take a long time to build, require deep crypto expertise and use custom software. Building app-specific rollups is even more difficult. Stackr aims to solve this problem with an SDK for building app-specific rollups, which enables developers to easily customize execution environments to fit their use cases.
Key takeaway: Appchains with custom state machines and storage can get up to 30x more efficiency vs. running a full VM (e.g. Arbitrum). In this model, the apps don't run on L2s but they are the "L2s". It’s worth noting that this model works best for apps and app ecosystems that only need asynchronous composability.
Personal recommendations from our team:
📚Reading: Cixin Liu - The Three-Body Problem: If you are looking for some summer reading, this trilogy is favoured by many of our team members!
💡Other: As AI keeps getting smarter, so do robot checks 🧐
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