Aztec Network
1 Sep
## min read

Q&A with Aztec Developer Advocate, Meredith Darden

A Q&A sessiondiscussing Meredith's background, role at Aztec, and insights on the evolution of the blockchain industry.

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Written by
Alysa Gill
Edited by

7 years of experience building blockchain communities. Privacy advocate. Previously at Oasis Network.

Alyssa (Aztec): Hey Meredith! So the idea of this interview is to get a sense of your career path, your role at Aztec, and what you’re excited about as a new member of our commercial team! Can you start by sharing your web2 background and how it helped lead you to web3?

Hi there, and yes! I was previously working in real estate, and funny enough I was an Assistant Leasing Manager for ~7 apartment complexes here in Baton Rouge. In a way, I was “Community Manager” — doing web3 marketing and other leasing work.

I wanted to start investing, but wasn’t exactly sure about what to invest in. I started doing copious amounts of research and stumbled upon crypto. I had heard of it like most people, had seen it in the news, and just generally heard all the crazy stories about how crypto was being used back in those days. This was around 2016, and I was young and excited.

Alyssa: How about what falling down the web3 rabbit hole looked like for you?

It took me a while to piece together what a smart contract or protocol was, and why these systems made sense for this transparent blockchain context as opposed to what we have in web2 — where everything is off-chain and we don’t have much control or flexibility.

Once I really started understanding what this technology meant for the future of society, for my children, I was inspired. I was working full time, mom of two, and staying up until 2:00 or 3:00am every single night on Reddit, on Facebook groups, on Twitter. Learning everything that I could — reading white papers. Since then, I’ve remained extremely passionate and curious.

Alyssa: How do you feel about the industry’s evolution over the past ~8 years?

Of course there’ve been periods when I’ve been disappointed in the industry, and seen the exact behaviors that we wanted to avoid from the traditional finance sector/web2 world replicated in this space that I saw as a shining beacon.

But I’ve really enjoyed most of it, and now I’ve reached a point where I fully acknowledge that things are shifting rapidly, and people are going to make mistakes. Web3 is a place where we can learn and improve together.

Alyssa: Why did you decide to join Aztec?

I’m super passionate about privacy in general. I was previously working at another privacy project called Oasis. And before that, I did work for PIVX — also centered around privacy. This has been a major theme in my excitement about what blockchain means.

There’s this public side of things which is great. But to expand these really cool use cases, some degree of privacy is needed. Having more control over our privacy is an opportunity in web3.

I’ve been super passionate about projects that are building in this direction and I became involved with the Universal Privacy Alliance (UPA). That’s how I got Aztec-pilled.

Alyssa: Would love to hear more about how you got Aztec-pilled, what did connecting with the project and team look like?

I was already very impressed with Aztec when Bruno and I had the opportunity to work on an ETHDenver event together - it was a mini-summit that I organized with about seven other members of the UPA.

While we were in Denver, I went to the Aztec meetup and got to chat with some of the other teammates. I felt synergy as it was clear to me that this team cared about doing things the right way, not the easy way.

I’ve always wanted to serve a community actively working towards putting privacy tools in the hands of developers, so that privacy can be leveraged by everyone else. In my core, I want to make sure that I’m a part of that privacy piece, specifically. This is why joining Aztec — where we’re paving the way to programmable privacy — made sense for me.

Alyssa: What are you focused on as Developer Advocate and what do you enjoy most about the role? Would be great to hear more about your work right now.

Yea! The title Developer Advocate is a new one for me. I’ve had many different ones, and in web3 we’re often required to wear many hats.

I’ve been a Community Lead, Social Media Strategist, and Marketing Manager. I’ve also had plenty of different hybrid roles across the projects I’ve been fortunate to be involved with.

As a Developer Advocate, I believe my core responsibility is to speak up for developers and make sure their feedback is being heard by the internal Aztec team…

…and also educate developers about what we’re building. We accomplish this through Discord, community events, 1:1 meetings, diving into GitHub — looking far beneath the surface of what people say to try to piece together: Where are we lacking? How can we improve? And conveying that to our team.

Alyssa: What does a robust, healthy developer community for a project like ours look like? What does it have and what does it need to have?

We can learn from a book that Bruno recommended to me when I first started at Aztec, it’s called Producing Open Source Software. When you look at how this book outlines everything that matters for an open source software project, including building the community, you can learn a lot.

First of all, you want to have a place where people can openly and freely contribute in a way that make sense for them — not putting the barrier too high on how people can get involved, or the time commitment. If they want to tinker with Noir or Aztec for 30–45 minutes a week — they’re still welcomed in our community. We leave expectations at the door.

For any developers engaged with our community, of course we want to provide a supportive environment that includes educational content, tooling, funding, listening to their feedback, and connecting them with fellow devs. Also seeding inspiration/ideas.

If you have a developer community where people feel like they belong, heard, and accepted, that’s key.

Alyssa: Wow, it’s really inspiring to hear you talk about it. And what about beyond web3? Just general interests and maybe hobbies. Are they pretty tech focused given you work in blockhain?

I’m a big time reader. I’ve read 39 books this year, and I’m working on a couple more. It’s my little escape — I read a mix of fiction and non-fiction to balance things.

I’m learning how to garden as well. I live in the south so I’ve been growing okra, peas, tomatoes, and carrots. My garden is flourishing, so I’m happy about that!

I also very much enjoy cooking, taking care of my family — that’s not necessarily a hobby but definitely my primary interest…taking care of my 3 kiddos and teaching them.

I’m hoping to foster in them a curiosity about life, so a lot of my newer interests overlap with the stuff they want to do!

Alyssa: Aw, I bet. That’s awesome. Anything else you want to share? How can people keep up with you?

Anyone who’s interested in building on Aztec and/or using Noir, don’t be afraid to reach out. Don’t let what is a seemingly steep learning curve deter you from getting your feet wet.

If anyone is interested in building with us or just joining our developer community, and wants to learn about the resources available, they can reach out to me on Twitter (@merfymerf), on Telegram (@Meredithdarden), via email (meredith@aztecprotocol.com) — all are fine.

The link to join our Discord server can be found in the docs, I’m in there as well. I’d love to help out however I can.

Alyssa: Amazing. Thank you so much.

Thank you!

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Aztec Network
Aztec Network
28 Oct
xx min read

Your Favorite DeFi Apps, Now With Privacy

Every time you swap tokens on Uniswap, deposit into a yield vault, or vote in a DAO, you're broadcasting your moves to the world. Anyone can see what you own, where you trade, how much you invest, and when you move your money.

Tracking and analysis tools like Chainalysis and TRM are already extremely advanced, and will only grow stronger with advances in AI in the coming years. The implications of this are that the ‘pseudo-anonymous’ wallets on Ethereum are quickly becoming linked to real-world identities. This is concerning for protecting your personal privacy, but it’s also a major blocker in bringing institutions on-chain with full compliance for their users. 

Until now, your only option was to abandon your favorite apps and move to specialized privacy-focused apps or chains with varying degrees of privacy. You'd lose access to the DeFi ecosystem as you know it now, the liquidity you depend on, and the community you're part of. 

What if you could keep using Uniswap, Aave, Yearn, and every other app you love, but with your identity staying private? No switching chains. Just an incognito mode for your existing on-chain life? 

If you’ve been following Aztec for a while, you would be right to think about Aztec Connect here, which was hugely popular with $17M TVL and over 100,000 active wallets, but was sunset in 2024 to focus on bringing a general-purpose privacy network to life. 

Read on to learn how you’ll be able to import privacy to any L2, using one of the many privacy-focused bridges that are already built. 

The Aztec Network  

Aztec is a fully decentralized, privacy-preserving L2 on Ethereum. You can think of Aztec as a private world computer with full end-to-end programmable privacy. A private world computer extends Ethereum to add optional privacy at every level, from identity and transactions to the smart contracts themselves. 

On Aztec, every wallet is a smart contract that gives users complete control over which aspects they want to make public or keep private. 

Aztec is currently in Testnet, but will have multiple privacy-preserving bridges live for its mainnet launch, unlocking a myriad of privacy preserving features.

Bringing Privacy to You

Now, several bridges, including Wormhole, TRAIN, and Substance, are connecting Aztec to other chains, adding a privacy layer to the L2s you already use. Think of it as a secure tunnel between you and any DeFi app on Ethereum, Arbitrum, Base, Optimism, or other major chains.

Here's what changes: You can now use any DeFi protocol without revealing your identity. Furthermore, you can also unlock brand new features that take advantage of Aztec’s private smart contracts, like private DAO voting or private compliance checks. 

Here's what you can do:

  • Use DeFi without revealing your portfolio: trade on Uniswap or deposit into Yearn without broadcasting your strategy to the world
  • Donate to causes without being tracked: support projects on Base without linking donations to your identity
  • Vote in DAOs without others seeing your choices: participate in governance on Arbitrum while keeping your votes private
  • Prove you're legitimate without doxxing yourself: pass compliance checks or prove asset ownership without revealing which specific assets you hold
  • Access exclusive perks without revealing which NFTs you own: unlock token-gated content on Optimism without showing your entire collection

The apps stay where they are. Your liquidity stays where it is. Your community stays where it is. You just get a privacy upgrade.

How It Actually Works 

Let's follow Alice through a real example.

Alice wants to invest $1,000 USDC into a yield vault on Arbitrum without revealing her identity. 

Step 1: Alice Sends Funds Through Aztec

Alice moves her funds into Aztec's privacy layer. This could be done in one click directly in the app that she’s already using if the app has integrated one of the bridges. Think of this like dropping a sealed envelope into a secure mailbox. The funds enter a private space where transactions can't be tracked back to her wallet.

Step 2: The Funds Arrive at the DeFi Vault

Aztec routes Alice's funds to the Yearn vault on Arbitrum. The vault sees a deposit and issues yield-earning tokens. But there's no way to trace those tokens back to Alice's original wallet. Others can see someone made a deposit, but they have no idea who.

Step 3: Alice Gets Her Tokens Back Privately

The yield tokens arrive in Alice's private Aztec wallet. She can hold them, trade them privately, or eventually withdraw them, without anyone connecting the dots.

Step 4: Alice Earns Yield With Complete Privacy

Alice is earning yield on Arbitrum using the exact same vault as everyone else. But while other users broadcast their entire investment strategy, Alice's moves remain private. 

The difference looks like this:

Without privacy: "Wallet 0x742d...89ab deposited $5,000 into Yearn vault at 2:47 PM"

With Aztec privacy: "Someone deposited funds into Yearn vault" (but who? from where? how much? unknowable).

In the future, we expect apps to directly integrate Aztec, making this experience seamless for you as a user. 

The Developers Behind the Bridges 

While Aztec is still in Testnet, multiple teams are already building bridges right now in preparation for the mainnet launch.

Projects like Substance Labs, Train, and Wormhole are creating connections between Aztec and major chains like Optimism, Unichain, Solana, and Aptos. This means you'll soon have private access to DeFi across nearly every major ecosystem.

Aztec has also launched a dedicated cross-chain catalyst program to support developers with grants to build additional bridges and apps. 

Unifying Liquidity Across Ethereum L2s

L2s have sometimes received criticism for fragmenting liquidity across chains. Aztec is taking a different approach. Instead, Aztec is bringing privacy to the liquidity that already exists. Your funds stay on Arbitrum, Optimism, Base, wherever the deepest pools and best apps already live. Aztec doesn't compete for liquidity, it adds privacy to existing liquidity.

You can access Uniswap's billions in trading volume. You can tap into Aave's massive lending pools. You can deposit into Yearn's established vaults, all without moving liquidity away from where it's most useful.

The Future of Private DeFi

We’re rolling out a new approach to how we think about L2s on Ethereum. Rather than forcing users to choose between privacy and access to the best DeFi applications, we’re making privacy a feature you can add to any protocol you're already using. As more bridges go live and applications integrate Aztec directly, using DeFi privately will become as simple as clicking a button—no technical knowledge required, no compromise on the apps and liquidity you depend on.

While Aztec is currently in testnet, the infrastructure is rapidly taking shape. With multiple bridge providers building connections to major chains and a dedicated catalyst program supporting developers, the path to mainnet is clear. Soon, you'll be able to protect your privacy while still participating fully in the Ethereum ecosystem. 

If you’re a developer and want a full technical breakdown, check out this post. To stay up to date with the latest updates for network operators, join the Aztec Discord and follow Aztec on X.

Aztec Network
Aztec Network
22 Oct
xx min read

Bringing Private Over-The-Counter (OTC) Swaps to Crypto

Transparent OTC Trades Are Holding the Industry Back

OTC trading is fundamental to how crypto markets function. It enables better price negotiations than what you'll find on public order books and facilitates trading of illiquid assets that barely exist on exchanges. Without OTC markets, institutional crypto trading would be nearly impossible. But here's the massive problem: every single OTC transaction leaves a permanent, public trace. 

Let's say you're a fund manager who needs to sell 1,000 BTC for USDC on Base. In a traditional OTC trade, your Bitcoin leaves your wallet and becomes visible to everyone on Bitcoin's blockchain. Through cross-chain settlement, USDC then arrives in your Base wallet, which is also visible to everyone on Base's blockchain. 

At this point, block explorers and analytics firms can connect these transactions through pattern analysis. As a result, your trading patterns, position sizes, and timing become public data, exposing your entire strategy.

This isn't just about privacy; transparent OTC creates serious operational and strategic risks. These same concerns have moved a significant portion of traditional markets to private off-exchange trades. 

Why Traditional Finance Moved to Private Markets

In TradFi, institutions don't execute large trades on public order books for many reasons. In fact, ~13% of all stocks in the US are now traded in dark pools, and more than 50% of trades are now off-exchange. 

They use private networks, dark pools, and OTC desks specifically because:

  • Strategy Protection: Your competitors can't front-run your moves
  • Better Execution: No market impact from revealing large positions
  • Regulatory Compliance: Meet reporting requirements without public disclosure
  • Operational Security: Protect proprietary trading algorithms and relationships

While OTC trading is already a major part of the crypto industry, without privacy, true institutional participation will never be practical. 

Now, Aztec is making this possible. 

Moving Whale-Sized Bags Privately on Aztec

We built an open-source private OTC trading system using Aztec Network's programmable privacy features. Because Aztec allows users to have private, programmable, and composable private state, users aren’t limited to only owning and transferring digital assets privately, but also programming and composing them via smart contracts.

If you’re new to Aztec, you can think of the network as a private world computer, with full end-to-end programmable privacy. A private world computer extends Ethereum to add optional privacy at every level, from identity and transactions to the smart contracts themselves. 

To build a private OTC desk, we leveraged all these tools provided by Aztec to implement a working proof of concept. Our private OTC desk is non-custodial and leverages private smart contracts and client-side proving to allow for complete privacy of the seller and buyer of the OTC.

How It Actually Works

For Sellers:

  1. Deploy a private escrow contract (only you know it exists at this stage)
  2. Initialize contract and set the terms (asset type, quantity, price)
  3. Deposit your assets into the contract
  4. After it’s been deployed, call a private API (the order book service)

For Buyers:

  1. Discover available orders through our privacy-preserving API
  2. Select trades that match your criteria
  3. Complete the seller's partial note with your payment
  4. Execute atomic swap – you get their assets, they get your payment

The Magic: Partial Notes are the technical breakthrough that make collaborative, asynchronous private transactions possible. Sellers create incomplete payment commitments that buyers can finish without revealing the seller's identity. It's like leaving a blank check that only the right person can cash, but neither party knows who the other is.

Privacy guarantees include: 

  • Complete Privacy: Neither party knows who they're trading with
  • Strategy Protection: Your trading patterns stay private
  • Market Impact Minimization: No public signals about large movements
  • Non-custodial: Direct peer-to-peer settlement, no intermediaries

Key Innovations

Private Contract Deployment: Unlike public decentralized exchanges where smart contracts are visible on the blockchain, the escrow contracts in this system are deployed privately, meaning that only the participants involved in the transaction know these contracts exist.

Partial Note Mechanism: This system uses cryptographic primitives that enable incomplete commitments to be finalized or completed by third parties, all while preventing those third parties from revealing or accessing any pre-existing information that was part of the original commitment.

Privacy-Preserving Discovery: The orderflow service maintains knowledge of aggregate trading volumes and overall market activity, but it cannot see the details of individual traders, including their specific trade parameters or personal identities.

Atomic Execution: The smart contract logic is designed to ensure that both sides of a trade occur simultaneously in a single atomic operation, meaning that if any part of the transaction fails, the entire transaction is rolled back and neither party's assets are transferred.

Build with us!

Our prototype for this is open-sourced here, and you can read about the proof of concept directly from the developer here

We're inviting teams to explore, fork, and commercialize this idea. The infrastructure for private institutional trading needs to exist, and Aztec makes it possible today. Whether you're building a private DEX, upgrading your OTC desk, or exploring new DeFi primitives, this codebase is your starting point. 

The traditional finance world conducts trillions in private OTC trades. It's time to bring that scale to crypto, privately.

To stay up to date with the latest updates for network operators, join the Aztec Discord and follow Aztec on X.

Aztec Network
Aztec Network
15 Oct
xx min read

Your Private Money Yearns for a Private Economy

Watch this: Alice sends Zcash. Bob receives USDC on Aztec. Nobody, not even the system facilitating it, knows who Alice or Bob are.

And Bob can now do something with that money. Privately.

This is the connection between private money and a private economy where that money can actually be used.

Zcash has already achieved something monumental: truly private money. It’s the store of value that Bitcoin promised (but made transparent). Like, digital gold that actually stays hidden.

But here's the thing about gold - you don't buy coffee with gold bars. You need an economy where that value can flow, work, and grow. Privately.

Money Under the Mattress

While other projects are trying to bolt privacy onto existing chains as an afterthought, Zcash is one of the oldest privacy projects in Web3. It's achieved what dozens of projects are still chasing: a truly private store of value.

Total Shielded ZEC Value (USD): Sep 16 - Oct 14 | Source: zkp.baby/

This is critical infrastructure for freedom. The ability to store value privately is a fundamental right, a hedge against surveillance, and a given when using cash. We need a system that provides the same level of privacy guarantees as cash. Right now, there's over $1.1 billion sitting in Zcash's shielded pool, private wealth that's perfectly secure but essentially frozen.

Why frozen? Because the moment that shielded $ZEC tries to do anything beyond basic transfers: earn yield, get swapped for stablecoins, enter a liquidity pool, it must expose itself. The privacy in this format is destroyed.

This isn't Zcash's failure. They built exactly what they set out to build: the world's best private store of value. The failure is that the rest of crypto hasn't built where that value can actually work.

The Privacy Landscape Has an Imbalance

What happens when you want to do more than just send money? What happens when you want privacy after you transfer your money?

Private Digital Money (i.e., “Transfer Privacy,” largely solved by Zcash):

  • Zcash: est. 2016
  • Everyone else: building variants of digital money at the transaction or identity level
    • Monero
    • Ethereum privacy pools
    • 0xbow
    • Payy
    • Every privacy stablecoin project
    • Every confidential L2
    • Every privacy project you've ever heard of

Private World Computer (i.e., After-the-Transfer Privacy):

  • Aztec

Everyone else is competing to build better ways to hide money. Zcash has already built the private store of value, and Aztec has built the only way to use hidden money.

The Locked Liquidity Problem

Here's the trillion-dollar question: What good is private money if you can't use it?

Right now, Zcash's shielded pool contains billions in value. This is money in high-security vaults. But unlike gold in vaults that can be collateralized, borrowed against, or deployed, this private value just sits there.

Every $ZEC holder faces two impossible choices:

  1. Keep it shielded and forfeit all utility
  2. Unshield it to use it and forfeit all privacy

Our demo breaks this false sense of choice. For the first time, shielded value can move to a place where it remains private AND becomes useful.

The Private World Computer

Here's how you can identify whether you’re dealing with a private world computer, or just private digital money:

Without a private world computer (every other privacy solution):

  • Receive salary privately → Can't invest it
  • Store savings privately → Can't earn yield
  • Send money privately → Recipient can't use it privately

With a private world computer (only Aztec):

  • Receive salary privately → Invest it privately
  • Store savings privately → Earn APY privately
  • Send payment privately → Recipient spends it privately

This is basic financial common sense. Your money should grow. It should work. It should be useful.

The technical reality is that this requires private smart contracts. Aztec is building the only way to interact privately with smart contracts. These smart contracts themselves can remain completely hidden. Your private money can finally do what money is supposed to do: work for you.

What We Actually Built

Our demo proves these two worlds can connect:

  1. The Vault: Zcash
  2. The Engine: Aztec (where private money becomes useful)

We built the bridge between storing privately and doing privately.

The technical innovation - "partial notes" - are like temporary lockboxes that self-destruct after one use. Money can be put privately into these lockboxes, and a key can be privately handed to someone to unlock it. No one knows who put the money in, where the key came from, or who uses the key. You can read more about how they work here. But what matters isn't the mechanism. 

What matters is that Alice's Zcash can become Bob's working capital on Aztec without anyone knowing about either of them.

As a result, Bob receives USDC that he can:

  • Earn yield on
  • Trade with
  • Pay suppliers with
  • Build a business on
  • All privately

Why This Required Starting from Scratch (and 8 years of building)

You can't bolt privacy onto existing systems. You can't take Ethereum and make it private. You can't take a transparent smart contract platform and add privacy as a feature.

Aztec had to be built from the ground up as a private world computer because after-the-transfer privacy requires rethinking everything:

  • How state is managed
  • How contracts execute
  • How proofs are generated
  • How transactions are ordered

This is why there's only one name building fully private smart contracts. From the beginning, Aztec has been inspired by the work Zcash has done to create a private store of value. That’s what led to the vision for a private world computer.

Everyone else is iterating on the same transfer privacy problem. Aztec solves a fundamentally different problem.

The Obvious Future

Once you see it, you can't unsee it: Privacy without utility is only the first step.

Every privacy project will eventually need what Aztec built. Because their users will eventually ask: "Okay, my money is private... now what?"

  • Zcash users will want their $ZEC to earn yield
  • Privacy pool users will want to do more than just mix
  • Private stablecoin users will want to actually… use their stablecoins

This demo that connects Zcash to Aztec is the first connection between the old world (private transfers) and the new world (private everything else).

What This Means

For Zcash Holders: Your shielded $ZEC can finally do something without being exposed.

For Developers: Stop trying to build better mattresses to hide money under. Start building useful applications on the only platform that keeps them private. 

For the Industry: The privacy wars are over. There's transfer privacy (solved by Zcash) and after-the-transfer privacy (just Aztec).

What’s Next? 

This demo is live. The code is open source. The bridge between private money and useful private money exists.

But this is just the beginning. Every privacy project needs this bridge. Every private payment network needs somewhere for those payments to actually be used.

We're not competing with transfer privacy. We're continuing it.

Your private money yearns for the private economy.

Welcome to after-the-transfer privacy. Welcome to Aztec.

Aztec Network
Aztec Network
8 Oct
xx min read

Aztec: The Private World Computer

Privacy has emerged as a major driver for the crypto industry in 2025. We’ve seen the explosion of Zcash, the Ethereum Foundation’s refocusing of PSE, and the launch of Aztec’s testnet with over 24,000 validators powering the network. Many apps have also emerged to bring private transactions to Ethereum and Solana in various ways, and exciting technologies like ZKPassport that privately bring identity on-chain using Noir have become some of the most talked about developments for ushering in the next big movements to the space. 

Underpinning all of these developments is the emerging consensus that without privacy, blockchains will struggle to gain real-world adoption. 

Without privacy, institutions can’t bring assets on-chain in a compliant way or conduct complex swaps and trades without revealing their strategies. Without privacy, DeFi remains dominated and controlled by advanced traders who can see all upcoming transactions and manipulate the market. Without privacy, regular people will not want to move their lives on-chain for the entire world to see every detail about their every move. 

While there's been lots of talk about privacy, few can define it. In this piece we’ll outline the three pillars of privacy and gives you a framework for evaluating the privacy claims of any project. 

The Three Pillars of Privacy 

True privacy rests on three essential pillars: transaction privacy, identity privacy, and computational privacy. It is only when we have all three pillars that we see the emergence of a private world computer. 

Transaction: What is being sent?

Transaction privacy means that both inputs and outputs are not viewable by anyone other than the intended participants. Inputs include any asset, value, message, or function calldata that is being sent. Outputs include any state changes or transaction effects, or any transaction metadata caused by the transaction. Transaction privacy is often primarily achieved using a UTXO model (like Zcash or Aztec’s private state tree). If a project has only the option for this pillar, it can be said to be confidential, but not private. 

Identity: Who is involved?

Identity privacy means that the identities of those involved are not viewable by anyone other than the intended participants. This includes addresses or accounts and any information about the identity of the participants, such as tx.origin, msg.sender, or linking one’s private account to public accounts. Identity privacy can be achieved in several ways, including client-side proof generation that keeps all user info on the users’ devices. If a project has only the option for this pillar, it can be said to be anonymous, but not private. 

Computation: What happened? 

Computation privacy means that any activity that happens is not viewable by anyone other than the intended participants. This includes the contract code itself, function execution, contract address, and full callstack privacy. Additionally, any metadata generated by the transaction is able to be appropriately obfuscated (such as transaction effects, events are appropriately padded, inclusion block number are in appropriate sets). Callstack privacy includes which contracts you call, what functions in those contracts you’ve called, what the results of those functions were, any subsequent functions that will be called after, and what the inputs to the function were. A project must have the option for this pillar to do anything privately other than basic transactions. 

From private money to a private world computer 

Bitcoin ushered in a new paradigm of digital money. As a permissionless, peer-to-peer currency and store of value, it changed the way value could be sent around the world and who could participate. Ethereum expanded this vision to bring us the world computer, a decentralized, general-purpose blockchain with programmable smart contracts. 

Given the limitations of running a transparent blockchain that exposes all user activity, accounts, and assets, it was clear that adding the option to preserve privacy would unlock many benefits (and more closely resemble real cash). But this was a very challenging problem. Zcash was one of the first to extend Bitcoin’s functionality with optional privacy, unlocking a new privacy-preserving UTXO model for transacting privately. As we’ll see below, many of the current privacy-focused projects are working on similar kinds of private digital money for Ethereum or other chains. 

Now, Aztec is bringing us the final missing piece: a private world computer.

A private world computer is fully decentralized, programmable, and permissionless like Ethereum and has optional privacy at every level. In other words, Aztec is extending all the functionality of Ethereum with optional transaction, identity, and computational privacy. This is the only approach that enables fully compliant, decentralized applications to be built that preserve user privacy, a new design space that we see as ushering in the next Renaissance for the space. 

Where are we now? 

Private digital money

Private digital money emerges when you have the first two privacy pillars covered - transactions and identity - but you don’t have the third - computation. Almost all projects today that claim some level of privacy are working on private digital money. This includes everything from privacy pools on Ethereum and L2s to newly emerging payment L1s like Tempo and Arc that are developing various degrees of transaction privacy 

When it comes to digital money, privacy exists on a spectrum. If your identity is hidden but your transactions are visible, that's what we call anonymous. If your transactions are hidden but your identity is known, that's confidential. And when both your identity and transactions are protected, that's true privacy. Projects are working on many different approaches to implement this, from PSE to Payy using Noir, the zkDSL built to make it intuitive to build zk applications using familiar Rust-like syntax. 

The Private World Computer 

Private digital money is designed to make payments private, but any interaction with more complex smart contracts than a straightforward payment transaction is fully exposed. 

What if we also want to build decentralized private apps using smart contracts (usually multiple that talk to each other)? For this, you need all three privacy pillars: transaction, identity, and compute. 

If you have these three pillars covered and you have decentralization, you have built a private world computer. Without decentralization, you are vulnerable to censorship, privileged backdoors and inevitable centralized control that can compromise privacy guarantees. 

Aztec: the Private World Computer 

What exactly is a private world computer? A private world computer extends all the functionality of Ethereum with optional privacy at every level, so developers can easily control which aspects they want public or private and users can selectively disclose information. With Aztec, developers can build apps with optional transaction, identity, and compute privacy on a fully decentralized network. Below, we’ll break down the main components of a private world computer.

Private Smart Contracts 

A private world computer is powered by private smart contracts. Private smart contracts have fully optional privacy and also enable seamless public and private function interaction. 

Private smart contracts simply extend the functionality of regular smart contracts with added privacy. 

As a developer, you can easily designate which functions you want to keep private and which you want to make public. For example, a voting app might allow users to privately cast votes and publicly display the result. Private smart contracts can also interact privately with other smart contracts, without needing to make it public which contracts have interacted. 

Aztec’s Three Pillars of Privacy

Transaction: Aztec supports the optionality for fully private inputs, including messages, state, and function calldata. Private state is updated via a private UTXO state tree.

Identity: Using client-side proofs and function execution, Aztec can optionally keep all user info private, including tx.origin and msg.sender for transactions. 

Computation: The contract code itself, function execution, and call stack can all be kept private. This includes which contracts you call, what functions in those contracts you’ve called, what the results of those functions were, and what the inputs to the function were. 

Decentralization

A decentralized network must be made up of a permissionless network of operators who run the network and decide on upgrades. Aztec is run by a decentralized network of node operators who propose and attest to transactions. Rollup proofs on Aztec are also run by a decentralized prover network that can permissionlessly submit proofs and participate in block rewards. Finally, the Aztec network is governed by the sequencers, who propose, signal, vote, and execute network upgrades.

What Can You Build with a Private World Computer?

Private DeFi

A private world computer enables the creation of DeFi applications where accounts, transactions, order books, and swaps remain private. Users can protect their trading strategies and positions from public view, preventing front-running and maintaining competitive advantages. Additionally, users can bridge privately into cross-chain DeFi applications, allowing them to participate in DeFi across multiple blockchains while keeping their identity private despite being on an existing transparent blockchain.

Private Dark Pools

This technology makes it possible to bring institutional trading activity on-chain while maintaining the privacy that traditional finance requires. Institutions can privately trade with other institutions globally, without having to touch public markets, enjoying the benefits of blockchain technology such as fast settlement and reduced counterparty risk, without exposing their trading intentions or volumes to the broader market.

Private RWAs & Stablecoins

Organizations can bring client accounts and assets on-chain while maintaining full compliance. This infrastructure protects on-chain asset trading and settlement strategies, ensuring that sophisticated financial operations remain private. A private world computer also supports private stablecoin issuance and redemption, allowing financial institutions to manage digital currency operations without revealing sensitive business information.

Compliant Apps

Users have granular control over their privacy settings, allowing them to fine-tune privacy levels for their on-chain identity according to their specific needs. The system enables selective disclosure of on-chain activity, meaning users can choose to reveal certain transactions or holdings to regulators, auditors, or business partners while keeping other information private, meeting compliance requirements.

Let’s build

The shift from transparent blockchains to privacy-preserving infrastructure is the foundation for bringing the next billion users on-chain. Whether you're a developer building the future of private DeFi, an institution exploring compliant on-chain solutions, or simply someone who believes privacy is a fundamental right, now is the time to get involved.

Follow Aztec on X to stay updated on the latest developments in private smart contracts and decentralized privacy technology. Ready to contribute to the network? Run a node and help power the private world computer. 

The next Renaissance is here, and it’s being powered by the private world computer.