It’s becoming more and more normal to use blockchains directly as smart contracts proliferate in adoption. But in an environment where everyone uses them, people will expect unwavering performance, privacy, and security — and only Zero Knowledge cryptography can help achieve all three.
Zero Knowledge Proofs, or ZKPs for short, are an important branch of cryptography that’s been heavily adopted in many blockchain applications. They enable users to prove certain statements without revealing data, which can be useful both for scalability and privacy. An early example of their application is ZCash, a coin where zk-proofs are used to prove that a transaction is valid revealing the sender, the receiver, or the transaction amount — thus achieving full privacy.
As the on-chain landscape evolves, privacy and safety must keep pace to foster an open and trustworthy environment.
Vitalik Buterin, founder of Ethereum, has emphasized the importance of advanced ZKP systems since 2016, including them as cornerstones of the Ethereum roadmap.
In a recent post, Buterin presented a potentially more efficient algorithm for improving ZKPs and encouraged users and developers to explore and innovate further.
Zero Knowledge technology is a branch of fundamental science being spearheaded and funded primarily by crypto projects. Here, we will discuss several innovative projects that all contributed to the advancement of ZKPs.
Proof of SQL through Space and Time
Transparency is crucial for reliably analyzing data and using it, but it’s also potentially costly and dangerous, depending on the volume and sensitivity of the data.
Space and Time, a startup backed by Microsoft VC and Samsung Next, is focused on developing one of the most efficient ZK-proofs specifically for data retrieval.
It relies on a network of nodes to store and process data and, with its AI technology, it is able to provide very fast ZKP, relying on both on-chain and off-chain data. They’ve developed a system they call HTAP (Hybrid Transactional/Analytical Processing), which enables performing complex near real-time queries with data originating from a blockchain.
However, Space and Time’s most significant innovation lies in their implementation of Proof of SQL, a novel use of zero-knowledge proofs. This approach allows users to cryptographically validate the accuracy of SQL data queries, giving cryptographic trust to the data being gathered.
Such technology opens new frontiers to enhance both data processing and analysis, facilitating things like off-chain order books for DeFi protocols or reliable analytics and rankings for GameFi and NFTs — and in the future, probably many more applications in the real world.
Polygon Scales with the zkEVM
Polygon is known as a quick and cheap network, but it will still eventually reach the limitations of a basic L1 blockchain.
A multi-layer scaling approach helps balance large transaction loads, keeping transactions affordable for users. Polygon, for its own scalability path, has chosen to go all-in on ZK, acquiring multiple research and product teams working on advancing Zero Knowledge.
The Polygon zkEVM, launched in March 2023, was the first EVM-compatible Layer-2 using the zk-rollup technology to save on costs and improve performance.
The zk-rollup improves the scalability of the network by leveraging cryptographic techniques enabled by ZKPs to quickly verify the validity of data published to the chain. By compressing transaction data and verifying it with zk-proofs, the zkEVM is able to reduce gas fees by over 90%.
Aztec(s): the pioneers of blockchain privacy
Aztec is one of the better known blockchain privacy pioneers, having worked on advancing ZK technology for over 6 years now.
They’ve made significant contributions to the broader ZKP space over the years, for example by implementing PLONK, a proving system for ZKPs that was more powerful and decentralized than anything that came earlier (and yet has itself been superseded by now).
Aztec is working on both a scalable and a private L2, using ZKPs in full strength. It has previously implemented zk.money, a privacy layer for asset transfers that used a proprietary UTXO system.
The vision behind the project is to offer a fully private rollup, allowing people to store data and transactions privately on an encrypted blockchain. One of the more interesting and complex challenges faced by Aztec is the creation of Noir, a private smart contract language that would be compatible with circuits, or the basic building block of data that can be verified with ZKPs.
The project is set to soon launch a testnet of its private L2, finally giving a users a taste of its 6+ years of research and development.
zkSync Bet on Ethereum Scaling
ZkSync by Matter Labs is another “old” project that has pushed ZKP development forward. It focuses specifically on offering more affordable and quick transactions in the Ethereum ecosystem, such as with their flagship product zkSync Era.
zkSync Era is a zk-rollup that combines multiple transactions into a single proof processed off-chain, substantially increasing Ethereum’s transaction throughput.
Era was designed to be as EVM-compatible as possible while still not being an EVM itself. Nonetheless, it supports Solidity and Vyper languages, as well as tools like Hardhat and Foundry. It is also fully functional and performant without compromising on ZK proofing, enhancing the overall experience for developers and users.
It has focused on a more commercial approach, implementing the “Hyperchain” — a network of zkSync-based interconnected rollups that would let developers deploy their own high performance chains. It has also partnered with Space and Time to bring verifiable zkSync and hyperchain data to users, fostering collaboration between ZK industry peers.
The era of ZK is getting closer and closer. After years of hardcore development, many projects are now ready to come fully online and leverage the enormous benefits of this technology. The question now is: how will dApp developers make use of it?
