Noir
22 Mar
## min read

Zero-knowledge gaming with BattleZips x Noir

BattleZips and Noir partnered up for zero-knowledge gaming, showcasing encrypted gameplay on the blockchain.

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Building games of imperfect information with Aztec’s Noir language

Noir was conceived of as an open-source, universal zero knowledge language. It was always meant to make the experience of developing in zero-knowledge much more accessible, by:

  • having simple to read syntax that’s easy to reason about
  • abstracting away cryptographic concepts and security considerations
  • incorporating cryptographic libraries for commonly used crypto primitives

So when we heard about the Mach34 team and their work on BattleZips — a Battleship clone relying on zero-knowledge — we knew we had to work together.We met the Mach34 team after they placed at the ETHDenver 2022 hackathon with a Circom-written version of the classic Hasbro game Battleship.Shortly after we released Noir, they expressed ➡️ interest in rewriting Battlezips, providing us feedback, and creating a tutorial series on writing zk circuits and programs in Noir.

➡️ Watch the BattleZips-Noir YouTube series here.

We provided them an Aztec Grant in late 2022, and they were off to the races, culminating in showcasing the Noir-powered Battlezips running in the browser at our sponsored game night at ETHDenver 2023.

➡️ Play Battlezips in your browser.

Here’s an unabridged conversation with Mach34 on their experience building on Noir and what developers can expect building on the universal zk language.

A Noir-ish conversation with Mach34

Q: Tell us about BattleZips. How does the game use zero-knowledge cryptography?

A: BattleZips is a zero-knowledge implementation of the popular board game Battleship that uses proofs to shield ship positions. While this is by no means an original idea for a zero-knowledge application, Battleships was chosen as it is a simple but complete example of integrating arbitrary business logic in zero knowledge circuits.

By settling zero knowledge proofs in smart contracts, we can create novel digital and economic interactions that make the existing role of Information Escrow by third parties obsolete. BattleZips helped us understand how to apply zero knowledge proofs, and we hope the BattleZips-Noir course gives you the same advantages!

Q: What inspired you to start Mach 34 and develop BattleZips? Why explore Noir?

A: BattleZips marked the beginning of our journey into zero-knowledge cryptography and expanded our horizon on where this technology could be applied in real world use cases.

This is one of the factors that lead us to creating Mach 34. Mach 34 is a Web3 and ZK Software Consultancy. We chose to focus on mastering the web3 tech stack for the sake of expertise rather than a specific application. This enables us to explore any industry ripe for decentralization, growing our overall experience with the enterprise of web3.

Corporations and governments alike habitually abuse the authoritative topology of web2 networks; as Web3/ ZK Consultants, we have the means and the desire to help innovators usurp centralized processes and give sovereignty in cyberspace back to the users.

It is crucial that we stay up to date with the latest trends in this fast developing space to ensure we provide superior expertise to clients. Our prior experience writing proofs demonstrated to us that there is a significant variation between the different tools that exist, how rapidly they can be applied to an engineering problem, and what they accomplish. This led us to explore Noir upon its official release and see how it differentiated itself from pre-existing alternatives.

Q: How did you find the ease of usability of Noir compared to other zero-knowledge domain specific languages you’ve worked with?

A: Prior to Noir we used the Circom language and the Halo 2 proving system written in Rust. Proceeding from a first look at the Noir documentation to writing circuits was a fairly quick and straightforward process.

We thought that Noir lived up to most of what it promised in its introductory medium post. If one were to begin learning Noir without wanting to get bogged down in learning the inner workings of ZK and how circuits translate to proofs then they could certainly do so. It does a good job of abstracting away from the more complex aspects of the topic.

One thing that could improve the developer experience is ensuring that the nargo command-line tool and the Aztec NPM packages compile the same Noir version. This is an issue we ran into mid way through the development process that resulted in a refactor to ensure we could test our circuits with the Aztec NPM packages.

Q: As a full-stack development shop, how has the process of incorporating zk-cryptography changed the way you approach software development projects?

A: Our interest in zero-knowledge cryptography was one of the driving factors for starting Mach 34. Historically and to this day, one of the most sought after skills in the web3 space is the ability to write smart contracts.

Similarly as the past few years have shown, we believe enabling privacy and scalability in web3 applications is only going to become more and sought after and ultimately a necessity. In anticipation of this we have positioned ourselves at Mach 34 to have the skills and expertise necessary to help companies engineer ZK solutions.

Q: What kind of impact do you think Noir and other zero-knowledge domain specific languages will have on the broader software development community? Where do you see the industry going?

A: Noir and other ZK DSLs play a pivotal role in the proliferation of zero-knowledge cryptography by abstracting away from the underlying cryptographic principles.

As history shows, abstraction is absolutely necessary for any technology to become widely adopted. If engineers were never able to design high level programming languages from low-level opcodes then we would have far fewer and less effective software developers than we do today.

Once the complexity and thought is removed from the underlying components that make zero-knowledge cryptography possible in the first place, engineers have more time to think about applications that would benefit from ZK. It looks like we are about to enter an exciting phase where we will start to see more examples of the technology applied to real world use cases.

Q: What advice would you give to developers who are interested in learning more about zero-knowledge cryptography and how to use it in their projects?

A: This is definitely an exciting space to get involved in given it is still very much in its infancy. It is poised to solve issues related to privacy and scalability in public blockchains, as well as contexts out of web3 where there is currently a lack of much needed privacy.

This being said, resources for learning are still sparse and those that exist often have a technical complexity that can make them hard to digest. It can take quite a bit of patience and perseverance to become acclimated to this space but it is well worth the effort given that you are one of the individuals pioneering the ecosystem.

If you are a developer that has an interest in getting started in ZK then I think reading some high-level introductory materials would be a good starting point.

After a basic understanding is gained on the topic then exploring a DSL like Circom or Noir to write a simple circuit would be a beneficial next step.

Once it becomes clearer to you what can be accomplished and what tools are at your disposal then really the limit is what you can ideate. The cool thing is that there is still so much room for novel innovation that it could very well be the case no one has thought of your idea yet. Don’t sit idle and wait for things to develop further! Now is a great time to jump in!

Q: Are there any upcoming projects at Mach 34 that you can share with us that utilize zero-knowledge cryptography or other cutting-edge technologies?

A: Mach 34 has been researching and working towards constructing a “Zero-Knowledge State Channel”. While rollups offer fantastic scalability, we were put off by the need for a sequencer. Furthermore, aside from Aztec Connect and a few others, ZK Rollups do not have any private state. Thus, we began to explore how state channels might be repurposed with zero knowledge.

To open a ZK State Channel, parties will agree on the terms of the execution (like a smart contract). The channel initialization dictates what steps can be taken next, and by whom. Rather than posting every transaction on-chain, a state object is recursively built off-chain.

While previous state channel constructions had optimistic trust assumptions, we can leverage ZK to perform verifiable computations that have instant, trustless finality. Once a state channel has reached an end condition, the entire state execution is notarized by posting the state channel proof on-chain for all nodes to verify in zero knowledge.

This final proof further employs zero knowledge to hide most of the intermediate state; only pre-determined derived metrics or public outputs are made publicly available on-chain.

This has many interesting use-cases; we plan to demonstrate how this construction is useful for credit scoring by adding ELO scores to the State Channel version of BattleZips. This provides a verifiable metric that scores the performance of an individual without revealing any of their in-game moves.

We envision countless use-cases for ZK State Channels across all segments of web3. Undoubtedly, there are use-cases that we haven’t thought of. For this reason, all of our work on ZK State Channels is free and open source. While we intend to utilize the infrastructure for profit, we want to make sure that all possibilities are explored in service of the best possible future for web3 developers and users.

Q: What are some use cases you’re excited for?

A: One area of exciting potential outside of blockchain is how zero-knowledge can transform personal identification.

When providing personal ID, the majority of the time more information is conveyed than necessary. Proving one is of a legal drinking age need only confirm the person is above 21 years of age, yet sharing the ID divulges information such as street address and name.

Using zero knowledge proofs conceivably one could prove they are at least 21 without having to provide additional information. Another example is having to provide a social security number in a KYC process. Leaking a SSN number can have catastrophic consequences so one would prefer this is done as infrequently as possible. With ZK proofs instead one could prove they bear a SSN number without needing to reveal exactly what theirs is.

Explore the BattleZips project

We’re thrilled that the Mach34 team have done such a deep and candid dive into Noir’s capabilities, and their feedback has been invaluable.For developers interested in building on Noir, check out their well-documented BattleZips repo.

➡️ Explore the BattleZips Github repo and codebase.

Build on Noir

Interested in building zero-knowledge applications on Noir — or contributing to the open-source project?

Join Us

We’re always looking for talented engineers, cryptographers, and businesspeople to join Aztec. We are committed to bringing encryption to blockchain through our encrypted zkRollup, and we’ve raised over $125 million from the best investors in crypto, including a16z and Paradigm to do so. Come onboard.

➡️ See our open roles here.

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Aztec Network
Aztec Network
31 Mar
xx min read

Announcing the Alpha Network

Alpha is live: a fully feature-complete, privacy-first network. The infrastructure is in place, privacy is native to the protocol, and developers can now build truly private applications. 

Nine years ago, we set out to redesign blockchain for privacy. The goal: create a system institutions can adopt while giving users true control of their digital lives. Privacy band-aids are coming to Ethereum (someday), but it’s clear we need privacy now, and there’s an arms race underway to build it. Privacy is complex, it’s not a feature you can bolt-on as an afterthought. It demands a ground-up approach, deep tech stack integration, and complete decentralization.

In November 2025, the Aztec Ignition Chain went live as the first decentralized L2 on Ethereum, it’s the coordination layer that the execution layer sits on top of. The network is not operated by the Aztec Labs or the Aztec Foundation, it’s run by the community, making it the true backbone of Aztec. 

With the infrastructure in place and a unanimous community vote, the network enters Alpha. 

What is the Alpha Network?

Alpha is the first Layer 2 with a full execution environment for private smart contracts. All accounts, transactions, and the execution itself can be completely private. Developers can now choose what they want public and what they want to keep private while building with the three privacy pillars we have in place across data, identity, and compute.

These privacy pillars, which can be used individually or combined, break down into three core layers: 

  1. Data: The data you hold or send remains private, enabling use cases such as private transactions, RWAs, payments and stablecoins.
  2. Identity: Your identity remains private, enabling accounts that privately connect real world identities onchain, institutional compliance, or financial reporting where users selectively disclose information.
  3. Compute: The actions you take remain private, enabling applications in private finance, gaming, and beyond.

The Key Components  

Alpha is feature complete–meaning this is the only full-stack solution for adding privacy to your business or application. You build, and Aztec handles the cryptography under the hood. 

It’s Composable. Private-preserving contracts are not isolated; they can talk to each other and seamlessly blend both private and public state across contracts. Privacy can be preserved across contract calls for full callstack privacy. 

No backdoor access. Aztec is the only decentralized L2, and is launching as a fully decentralized rollup with a Layer 1 escape hatch.

It’s Compliant. Companies are missing out on the benefits of blockchains because transparent chains expose user data, while private networks protect it, but still offer fully customizable controls. Now they can build compliant apps that move value around the world instantly.

How Apps Work on Alpha 

  1. Write in Noir, an open-source Rust-like programming language for writing smart contracts. Build contracts with Aztec.nr and mark functions private or public.
  1. Prove on a device. Users execute private logic locally and a ZK proof is generated.
  1. Submit to Aztec. The proof goes to sequencers who validate without seeing the data. Any public aspects are then executed.
  1. Settle on Ethereum. Proofs of transactions on Aztec are settled to Ethereum L1.

Developers can explore our privacy primitives across data, identity, and compute and start building with them using the documentation here. Note that this is an early version of the network with known vulnerabilities, see this post for details. While this is the first iteration of the network, there will be several upgrades that secure and harden the network on our path to Beta. If you’d like to learn more about how you can integrate privacy into your project, reach out here

To hear directly from our Cofounders, join our live from Cannes Q&A on Tuesday, March 31st at 9:30 am ET. Follow us on X to get the latest updates from the Aztec Network.

Aztec Network
Aztec Network
27 Mar
xx min read

Critical Vulnerability in Alpha v4

On Wednesday 17 March 2026 our team discovered a new vulnerability in the Aztec Network. Following the analysis, the vulnerability has been confirmed as a critical vulnerability in accordance with our vulnerability matrix.

The vulnerability affects the proving system as a whole, and is not mitigated via public re-execution by the committee of validators. Exploitation can lead to severe disruption of the protocol and theft of user funds.

In accordance with our policy, fixes for the network will be packaged and distributed with the “v5” release of the network, currently planned for July 2026.

The actual bug and corresponding patch will not be publicly disclosed until “v5.”

Aztec applications and portals bridging assets from Layer 1s should warn users about the security guarantees of Alpha, in particular, reminding users not to put in funds they are not willing to lose. Portals or applications may add additional security measures or training wheels specific to their application or use case.

State of Alpha security

We will shortly establish a bug tracker to show the number and severity of bugs known to us in v4. The tracker will be updated as audits and security researchers discover issues. Each new alpha release will get its own tracker. This will allow developers and users to judge for themselves how they are willing to use the network, and we will use the tracker as a primary determinant for whether the network is ready for a "Beta" label.

Additional bug disclosure

We have identified a vulnerability in barretenberg allowing inclusion of incorrect proofs in the Aztec Network mempool, and ask all nodes to upgrade to versions v.4.1.2 or later.

We’d like to thank Consensys Diligence & TU Vienna for a recent discovery of a separate vulnerability in barretenberg categorized as medium for the network and critical for Noir:

We have published a fixed version of barretenberg.

We’d also like to thank Plainshift AI for discovery, reproduction, and reporting of one more vulnerability in the Aztec Network and their ongoing work to help secure the network.

Aztec Network
Aztec Network
18 Mar
xx min read

How Aztec Governance Works

Decentralization is not just a technical property of the Aztec Network, it is the governing principle. 

No single team, company, or individual controls how the network evolves. Upgrades are proposed in public, debated in the open, and approved by the people running the network. Decentralized sequencing, proving, and governance are hard-coded into the base protocol so that no central actor can unilaterally change the rules, censor transactions, or appropriate user value.

The governance framework that makes this possible has three moving parts: Aztec Improvement Proposal (AZIP), Aztec Upgrade Proposal (AZUP), and the onchain vote. Together, they form a pipeline that takes an idea to a live protocol change, with multiple independent checkpoints along the way.

The Virtual Town Square

Every upgrade starts with an AZIP. AZIPs are version-controlled design documents, publicly maintained on GitHub, modeled on the same EIP process that has governed Ethereum since its earliest days. Anyone is encouraged to suggest improvements to the Aztec Network protocol spec.

Before a formal proposal is opened, ideas live in GitHub Discussions, an open forum where the community can weigh in, challenge assumptions, and shape the direction of a proposal before it hardens into a spec. This is the virtual town square: the place where the network's future gets debated in public, not decided behind closed doors.

The AZIP framework is what decentralization looks like in practice. Multiple ideas can surface simultaneously, get stress-tested by the community, and the strongest ones naturally rise. Good arguments win, not titles or seniority. The process selects for quality discussion precisely because anyone can participate and everything is visible.

Once an AZIP is formalized as a pull request, it enters a structured lifecycle: Draft, Ready for Discussion, then Accepted or Rejected. Rejected AZIPs are not deleted — they remain permanently in the repository as a record of what was tried and why it was rejected. Nothing gets quietly buried.

Security Considerations are mandatory for all Core, Standard, and Economics AZIPs. Proposals without them cannot pass the Draft stage. Security is structural, not an afterthought.

From Proposal to Upgrade

Once Core Contributors, a merit-based and informal group of active protocol contributors, have reviewed an AZIP and approved it for inclusion, it gets bundled into an AZUP.

An AZUP takes everything an AZIP described and deploys it — a real smart contract, real onchain actions. Each AZUP includes a payload that encodes the exact onchain changes that will occur if the upgrade is approved. Anyone can inspect the payload on a block explorer and see precisely what will change before voting begins.

The payload then goes to sequencers for signaling. Sequencers are the backbone of the network. They propose blocks, attest to state, and serve as the first governance gate for any upgrade. A payload must accumulate enough signals from sequencers within a fixed round to advance. The people actually running the network have to express coordinated support before any change reaches a broader vote.

Once sequencers signal quorum, the proposal moves to tokenholders. Sequencers' staked voting power defaults to "yea" on proposals that came through the signaling path, meaning opposition must be active, not passive. Any sequencer or tokenholder who wants to vote against a proposal must explicitly re-delegate their stake before the voting snapshot is taken. The system rewards genuine engagement from all sides.

For a proposal to pass, it must meet quorum, a supermajority margin, and a minimum participation threshold, all three. If any condition is unmet, the proposal fails.

Built-In Delays, Built-In Safety

Even after a proposal passes, it does not execute immediately. A mandatory delay gives node operators time to deploy updated software, allows the community to perform final checks, and reduces the risk of sudden uncoordinated changes hitting the network. If the proposal is not executed within its grace period, it expires.

Failed AZUPs cannot be resubmitted. A new proposal must be created that directly addresses the feedback received. There is no way to simply retry and hope for a different result.

No Single Point of Control

The teams building the network have no special governance power. Sequencers, tokenholders, and Core Contributors are the governing actors, each playing a distinct and non-redundant role.

No single party can force or block an upgrade. Sequencers can withhold signals. Tokenholders can vote nay. Proposals not executed within the grace period expire on their own.

This is decentralization working as intended. The network upgrades not because a team decides it should, but because the people running it agree that it should.

If you want to help shape what Aztec becomes, the forum is open. The proposals are public. The town square is yours. 

Follow Aztec on X to stay up to date on the latest developments.

Aztec Network
Aztec Network
10 Mar
xx min read

Alpha Network Security: What to Expect

Aztec’s Approach to Security

Aztec is novel code — the bleeding edge of cryptography and blockchain technology. As the first decentralized L2 on Ethereum, Aztec is powered by a global network of sequencers and provers. Decentralization introduces some novel challenges in how security is addressed; there is no centralized sequencer to pause or a centralized entity who has power over the network. The rollout of the network reflects this, with distinct goals at each phase.

Ignition

Validate governance and decentralized block building work as intended on Ethereum Mainnet. 

Alpha

Enable transactions at 1TPS, ~6s block times and improve the security of the network via continual ongoing audits and bug bounty. New releases of the alpha network are expected regularly to address any security vulnerabilities. Please note, every alpha deployment is distinct and state is not migrated between Alpha releases. 

Beta

We will transition to Beta once the network scales to >10 TPS, with reduced block times while ensuring 99.9% uptime. Additionally, the transition requires no critical bugs disclosed via bug bounty in 3 months. State migrations across network releases can be considered.

TL;DR: The roadmap from Ignition to Alpha to Beta is designed to reflect the core team's growing confidence in the network's security.

This phased approach lets us balance ecosystem growth while building security confidence and steadily expanding the community of researchers and tools working to validate the network’s security, soundness and correctness.

Ultimately, time in production without an exploit is the most reliable indicator of how secure a codebase is.

At the start of Alpha, that confidence is still developing. The core team believes the network is secure enough to support early ecosystem use cases and handle small amounts of value. However this is experimental alpha software and users should not deposit more value than they are willing to lose. Apps may choose to limit deposit amounts to mitigate risk for users.

Audits are ongoing throughout Alpha, with the goal to achieve dual external audits across the entire codebase.

The table below shows current security and audit coverage at the time of writing.

The main bug bounty for the network is not yet live, other than for the non-cryptographic L1 smart contracts as audits are ongoing. We encourage security researchers to responsibly disclose findings in line with our security policy .

As the audits are still ongoing, we expect to discover vulnerabilities in various components. The fixes will be packaged and distributed with the “v5” release.

If we discover a Critical vulnerability in “v4” in accordance with the following severity matrix, which would require the change of verification keys to fix, we will first alert the portal operators to pause deposits and then post a message on the forum, stating that the rollup has a vulnerability.

Security of the Aztec Virtual Machine (AVM)

Aztec uses a hybrid execution model, handling private and public execution separately — and the security considerations differ between them.

As per the audit table above, it is clear that the Aztec Virtual Machine (AVM) has not yet completed its internal and external audits. This is intentional as all AVM execution is public, which allows it to benefit from a “Training Wheel” — the validator re-execution committee.

Every 72 seconds, a collection of newly proposed Aztec blocks are bundled into a "checkpoint" and submitted to L1. With each proposed checkpoint, a committee of 48 staking validators randomly selected from the entire set of validators (presently 3,959) re-execute all txs of all blocks in the checkpoint, and attest to the resulting state roots. 33 out of 48 attestations are required for the checkpoint proposal to be considered valid. The committee and the eventual zk proof must agree on the resultant state root for a checkpoint to be added to the proven chain. As a result, an attacker must control 33/48 of any given committee to exploit any bug in the AVM.

The only time the re-execution committee is not active is during the escape hatch, where the cost to propose a block is set at a level which attempts to quantify the security of the execution training wheel. For this version of the alpha network, this is set a 332M AZTEC, a figure intended to approximate the economic protection the committee normally provides, equivalent to roughly 19% of the un-staked circulating supply at the time of writing. Since the Aztec Foundation holds a significant portion of that supply, the effective threshold is considerably higher in practice.

Quantifying the cost of committee takeover attacks

A key design assumption is that just-in-time bribery of the sequencer committee is impractical and the only ****realistic attack vector is stake acquisition, not bribery.

Assuming a sequencer set size of 4,000 and a committee that rotates each epoch (~38.4mins) from the full sequencer set using a Fisher-Yates shuffle seeded by L1 RANDAO we can see the probability and amount of stake required in the table below.

To achieve a 99% probability of controlling at least one supermajority within 3 days, an attacker would need to control approximately 55.4% of the validator set - roughly 2,215 sequencers representing 443M AZTEC in stake. Assuming an exploit is successful their stake would likely de-value by 70-80%, resulting in an expected economic loss of approximately 332M AZTEC.

To achieve only a 0.5% probability of controlling at least one supermajority within 6 months, an attacker would need to control approximately 33.88% of the validator set.

What does this means for builders?

The practical effect of this training wheel is that the network can exist while there are known security issues with the AVM, as long as the value an attacker would gain from any potential exploit is less than the cost of acquiring 332M AZTEC.

The training wheel allows security researchers to spend more time on the private execution paths that don’t benefit from the training wheel and for the network to be deployed in an alpha version where security researchers can attempt to find additional AVM exploits.

In concrete terms, the training wheel means the Alpha network can reasonably secure value up to around 332M AZTEC (~$6.5M at the time of writing).

Ecosystem builders should keep the above limits in mind, particularly when designing portal contracts that bridge funds into the network.

Portals are the main way value will be bridged into the alpha network, and as a result are also the main target for any exploits. The design of portals can allow the network to secure far higher value. If a portal secures > 332M AZTEC and allows all of its funds to be taken in one withdrawal without any rate limits, delays or pause functionality then it is a target for an AVM exploit attack.

If a portal implements a maximum withdrawal per user, pause functionality or delays for larger withdrawals it becomes harder for an attacker to steal a large quantum of funds in one go.

Conclusion

The Aztec Alpha code is ready to go. The next step is for someone in the community to submit a governance proposal and for the network to vote on enabling transactions. This is decentralization working as intended.

Once live, Alpha will run at 1 TPS with roughly 6 second block times. Audits are still ongoing across several components, so keep deposits small and only put in what you're comfortable losing.

On the security side, a 48-validator re-execution committee provides the main protection during Alpha, requiring 33/48 consensus on every 72-second checkpoint. Successfully attacking the AVM would require controlling roughly 55% of the validator set at a cost of around 332M AZTEC, putting the practical security ceiling at approximately $6.5M.

Alpha is about growing the ecosystem, expanding the security of the network, and accumulating the one thing no audit can shortcut: time in production. This is the network maturing in exactly the way it was designed to as it progresses toward Beta.