In the world of cryptography and privacy-first blockchain innovation, few names carry as much weight as Howard Wu. From co-authoring foundational protocols like Zexe and DIZK to launching Aleo, a Layer 1 blockchain built from the ground up for programmable privacy, Wu has emerged as a core architect of the zero-knowledge (ZK) movement.

In this edition of HackerNoon's "Behind the Startup", Ishan Pandey sits down with Howard Wu to explore the roots of Aleo, the evolution of ZK cryptography, the interplay between compliance and privacy, and why the personal computing revolution in Web3 may have already begun.

Ishan Pandey: Hi Howard, it's a pleasure to welcome you to our "Behind the Startup" series. Tell us a bit about your background in cryptography and what led you to start Aleo?

Howard Wu: Hi Ishan, thank you for having me. My interest in cryptography goes beyond a pure fascination with mathematics - it is a fundamental desire to define what trust means. This has implications throughout our daily lives, including how to best protect our personal data online and in the real world.

If we are going to take advantage of all the conveniences the web has to offer, how can we be safe? More than 5 billion people use the internet today. That’s trillions of personally identifiable data – home addresses, social security numbers, credit card numbers, and even more deeply personal information like medical records.

I had the privilege of working with Professor Alessandro Chiesa and Professor Dawn Song as an undergraduate and graduate researcher at UC Berkeley. During my time at Berkeley, I co-authored the Zexe research paper, which stands for Zero-Knowledge Executions, alongside Professor Chiesa and fellow top minds in ZK cryptography. Together, we then started Aleo and set out to create a blockchain that was scalable, private and programmable, giving developers the ability to bake zero-knowledge into applications for the most critical use cases including payments, identity, and defi.

Ishan Pandey: Your work on Zexe and DIZK is foundational in the ZK world. How did your academic research evolve into real-world cryptographic infrastructure adopted by major protocols?

Howard Wu: I knew during my graduate studies that I wanted to make an impact in the real-world with my research work. When we published the Zexe research paper, I received a huge amount of inbounds from decentralized protocols and VCs alike. Ethereum’s co-founder Vitalik asked me to launch Zexe on Ethereum, and DeFi protocols like Uniswap & Kyber wanted to use Zexe to build decentralized dark pools.

With the amount of inbound interest we received, I decided to take a leap of faith to commercialize Zexe. We named the company Aleo, which stands for Autonomous Ledger Executions Off-chain. Our goal was simple: Bitcoin brought decentralization, Ethereum brought programmability, & Zcash brought privacy. Aleo was here to bring all three.

After receiving initial seed funding from notable Silicon Valley VCs, we were off on our mission to build private smart contracts and introduce this entire new paradigm to the world of crypto. We spent the first three years building, testing, and validating our architecture. Namely, we wanted to design a decentralized system that was scalable, confidential, and interoperable with the rest of crypto. And in our fourth year, we did just that and launched Aleo with Coinbase and HashKey as our Day-1 launch partners.

Ishan Pandey: Aleo is building a fully private, programmable blockchain using zero-knowledge proofs. What were the key technical and philosophical challenges in designing a platform that balances privacy, performance, and developer usability?

Howard Wu: From 2019 to early 2020, we spent almost a year figuring out how to deploy Zexe onto Ethereum. We worked with folks from the Ethereum Foundation and community grants team to explore what it would take to deploy a fully private system like Zexe onto Ethereum.

In the process, we learned a very hard truth. Privacy is incredibly difficult to achieve on a public-by-default blockchain. For instance, because Ethereum utilized an account-based model, every transaction’s gas had to be paid for publicly by a publicly-known address. And worse, the blockchain itself had no primitives to support the encryption and decryption of private state. We were inheriting the design tradeoffs of a bit-based system when we realized the future of crypto was algebraic. The ability to introduce true privacy for users and applications were near impossible and cost-prohibitive to achieve on Ethereum.

From this, we realized we needed to build an L1 from the ground up. We needed to build an L1 that was private-by-default, ZK-friendly, and intuitive for non-cryptographers in order to showcase the true power of ZK. From day-1, our focus has been to ensure developers – without a PhD in mathematics or cryptography – could write, deploy, and run private smart contracts without friction. We iterated for years to ensure our blockchain architecture made private state management and data availability (DA) intuitive and manageable for our developers.

Ishan Pandey: With Provable, you're now focusing on compliant, confidential payments. Why do you believe compliance and privacy don't have to be mutually exclusive—and how does Provable achieve this balance?

Howard Wu: Real-world crypto payments won’t achieve mass adoption until we offer transactional privacy for the end user. I often like to share how there’s amazing benefits associated with paying vendors in crypto - faster settlement times, easier cross-border payments - but the drawbacks are huge. Nobody wants all of their information from their transactions out in the open for everyone, including competitors, data scientists, and governments, to see.

Aleo introduces compliance at every level of the protocol stack. For example, every account on Aleo is protected by an account view key, which can decrypt and read transaction information. It allows compliance departments to offer a separation of responsibilities and on-chain access control to appropriate parties. For instance, you may want to give an entry-level software engineer visibility into the transaction graph and metadata, while allowing fraud or compliance teams to use view keys to access transaction history.

Ishan Pandey: Aleo introduces a new model of application deployment compared to EVM-based systems. What changes when developers build on Aleo, and how do zero-knowledge proofs change the dApp paradigm?

Howard Wu: Ethereum was not designed to be privacy first – like most blockchains, it was built with transparency at its core. And like most blockchains, Ethereum operates like a mainframe. Users timeshare this fully-public world computer to run their code in 100ms time slices. This architecture neither scales nor offers privacy for its users.

Aleo is built to scale user transactions and offer them true privacy using ZK cryptography. Instead of re-executing every transaction on the blockchain, on Aleo, users submit transactions with a ZK proof of execution, allowing the network to merely verify that the transaction was executed properly.

In doing so, where Ethereum is a mainframe, Aleo introduces the personal computing revolution. You run your own computations, you protect your personal data, and you decide what gets shared with the public network. It’s a truly powerful paradigm shift for crypto.

Ishan Pandey: We're seeing a wave of zk innovation—from zkVMs to recursive proof systems. What do you see as the next major breakthrough in zero-knowledge cryptography, and what’s overhyped?

Howard Wu: The last 2 years has been an exciting time for ZK researchers and developers. The growth in interest for ZK technology has been exponential. And the use cases for ZK have increased dramatically.

I believe ZK will be a bridge between Web2 systems and Web3 platforms. For instance, the rise of recent advances in ZK identity solutions shows how ZK is an answer to many of the growing challenges of the web. You can now use ZK to offer age verification. Namely, you can attest to the fact that you are over the age of 18 without revealing your date of birth to everyone on the public web. In addition, ZK allows you to prove that you aren’t from an OFAC sanctioned country, without revealing your nationality. This extends ZK into the territory of KYC/AML, where the stakes for compliance and financial safety are high.

Ishan Pandey: Many privacy-oriented chains struggle with adoption due to developer complexity or regulatory uncertainty. What strategies is Aleo using to onboard both developers and real-world use cases?

Howard Wu: Aleo is committed to growing and educating the next generation of web3 developers so that people worldwide can experience the power of ZK cryptography for themselves. Our CodeSprint hackathon encourages developers to compete by building dApps in critical areas, including private compliant stablecoins, verifiable private state and defi use cases like lending and borrowing protocols. We’ll be announcing the latest round of winners soon.

We have also partnered with Google Cloud to provide developers with ZK infrastructure and datasets, such as our One-Click Node Deployment in its marketplace, integration of Aleo’s blockchain data into Google BigQuery, and grants from the Google Cloud for Startups program.

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