Aztec Network
Dec 11th, 2023
## min read

Announcing the Aztec Sandbox Alpha Program

Share
Written by
Jon Wu
Edited by

Supporting the earliest builders on Aztec’s privacy-first Layer 2

In September, Aztec Labs launched the Aztec Sandbox, a prototype local developer testnet for privacy-first applications on the Aztec network.

Shortly thereafter, we recruited a small group of dedicated blockchain and ZK developers to a friendly, closed-invite feedback partnership program.

We had three goals for this program:

  1. Improve developer experience with added features
  2. Stabilize the Sandbox with bug reports and technical feedback
  3. Encourage experimentation and development of novel applications using the Sandbox’s Private Execution Environment (PXE) and public-private state management functionality

We’re now wrapping up the first round of closed-invite Sandbox feedback partnerships, with two more rounds to come, before we gear up for an open testnet launch.

We believe the Sandbox environment is alpha-ready: stable, well-documented, and well-featured enough for dedicated partners to use.

As a result, we are opening the alpha to developers in a hands-on program. Experience with Noir, Aztec, or Sandbox is strongly preferred but not necessary.

The Program

{{blog_divider}}

Of course non-men are also wanted.

The Sandbox Alpha Program is meant to onboard the earliest, most hardcore, and most dedicated privacy-first developers. No prior experience with Noir, Aztec, or ZK is necessary, but alpha partners will need to have:

  • Exceptional technical skills
  • Ability to commit 15-20 hours a week for ~4-6 weeks
  • Regular check-ins with the Aztec Labs core team

In return, alpha partners will receive:

  • A modest stipend
  • Comarketing support
  • A dedicated core Aztec protocol engineer as a partner
  • Opportunity to be a highly valued member of the Aztec community and join early to voice your feedback in the development of our network
  • Help from the Aztec core team in building fully-fledged Aztec applications on Aztec’s eventual mainnet
  • And, of course, honor and glory

📝 If you’re interested in becoming an Alpha partner, apply here:

What’s so special about Aztec?

Aztec is a privacy-first layer 2 on Ethereum. What that means is Aztec enables:

  • Reading and writing smart contract data to private storage
  • Private execution of smart contract functions
  • Public-private state interactions in the same transaction

Aztec also comes with private L1<>L2 messaging functionality and native account abstraction.

Practically, smart contracts can store public information, legible to all, and also write information to private, encrypted datastores.

Users–and only users–are able to retrieve their own private data and compute over that data locally, on their own devices.

This not only establishes ironclad privacy, but enables broad new blockchain functionality. For starters, Aztec easily enables identity privacy, meaning every transaction in Aztec can start privately (from your account contract) which can then execute functions privately or publicly.

A dapp can have private and public methods in the same contract, with public-private contract calls.Aztec has identity privacy by default. Meaning even when applications are deployed to public memory, users can interact with those applications privately.

Feedback Partners Proofs of Concept

The design space for private applications goes far beyond “DeFi but private” or “NFTs but private” given that fully encrypted data ownership (“private state”) is now a reality.

Here are just some of the example projects built in the Sandbox during our closed-door feedback round:

Ikigai (web3 Patreon) - Resurgence Labs

As an example, take Resurgence Labs, who are building a project called Ikigai, a private web3 version of Patreon. The way Patreon works in web2 is individuals commit funds on a recurring basis to Patreon, unlocking rewards. Payments are verified using a web2 payment API (e.g. Stripe), allowing access to paywalled content.

👀 See the Ikigai project Github here.

How would you build a Patreon like service on Ethereum without forcing individuals to leak their subscriptions? For instance, on Ethereum everyone can see your address sending payments to your chosen creators.

Using the Aztec Sandbox, Resurgence Labs created a smart contract that allows individuals to purchase a private NFT–kept in one’s own encrypted datastore, which when proven to Ikigai, grants access to gated premium content.

The contract first mints an encrypted NFT with details of the subscription. At any time, the NFT owner can prove ownership and non-expiry of the NFT to Ikigai’s server.

“Unlike most web3 dapps, we can actually cite something other than decentralization as our USP over our web2 counterpart (say Patreon). With this feature, people can subscribe to something without having to let the world know about it (or be judged over it).”

Private Optimistic Oracle - DeFi Wonderland

Wonderland built a private ask-and-answer platform on which a requester can pose a private query for information. This query is encrypted specifically for a third party that can furnish answers for the requester, and all questions and responses are kept private to everyone but the involved parties.

👀 See DeFi Wonderland's Github projects here, here, and here.

The requester escrows funds privately to a contract, where the answerer can eventually redeem the funds, without any established relationship between the requester and the answerer.

Wonderland’s design opens up significant opportunities across messaging and oracle services:

Not only can individuals privately request information and data on-chain, but they can also exchange funds attached to answers furnished.

The notion that two parties can privately escrow funds in advance of a unilateral transaction is a powerful primitive we think could be used in everything from oracles to on-chain legal contracts and business agreements.

Zybil, a Sybil-Resistant Identity Protocol - Mach34

Mach34 created a mock of a Gitcoin Passport-style Sybil Resistance protocol that allows the creation of a sybil resistance score that encrypts “stamps” of data ingested from various web2 and web3 sources. By aggregating stamps, a public sybil score can be created for use in other applications, proving you meet a minimum sybil score without revealing the individual data sources used. Users can also post encrypted attestations to identity back to L1.

👀 See Mach34's project Github here.

In the future, such functionality can be extended to things like legal identities which could confer proof of age, residency, or other personal identifiable information without privacy leakage.

Aztec Labs has always believed provable attestations and identity would be a significant step ahead in securing blockchains, improving fair token distributions, and unlocking DeFi primitives like undercollateralized lending.

Imagine identity passports with completely private attestations, any combination of which a protocol can request in order for the user to access additional functionality.

Private On-Chain Poker - Zach Obront

Poker is a trivial game to design in a trusted game environment. A trusted dealer custodies face-down cards, shuffles them, and deals them to players. Players assume fairness in shuffling and distribution.

👀 See Zach's project Github here.

Zach Obront is an Aztec Labs grantee who developed a poker game with no centralized, trusted dealer. The players cryptographically generate the deck and use Aztec’s infrastructure to keep their cards private while performing betting and hand resolution logic.

  • Each player generates a secret key, derives a public key, and posts proof that they know the secret key corresponding with the public key.
  • Each player takes turns shuffling the order of the cards, and then encrypting the value. They submit a ZK proof that the shuffle was done legitimately.
  • After all players have shuffled, no group (except the whole table) could have colluded to know which encrypted value corresponds to which card, and all cards are encrypted with the aggregate public key.
  • To deal the cards, we count off which card belongs to which player, and everyone else decrypts it. Then the player can privately decrypt to view the card.

While playing fully on-chain poker is likely too transaction- and latency-intensive to be feasible, we believe such a design could be implemented using state channels (where the end state of the hand is settled on-chain) or an L3 built on top of Aztec.

“ZK proof of correct shuffle is as easy as a for loop. That would have been the bottleneck to the whole thing working in any other environment.”
– Zach Obront on choosing Aztec

Join the Feedback Program

We want to work with dedicated, privacy-first individuals and teams who are willing to commit to working with Aztec’s infrastructure on a collaborative and open basis.

We are at the frontier of blockchain privacy. So to paraphrase Ernest Shackleton, Antarctic explorer:

DEVS WANTED

  • For hazardous journey, small wages, bitter bugs, long months of debugging, constant updates, working code doubtful, honor and recognition in case of success

What we’re looking for

  • Prior experience with building apps/infra either for blockchains or the ZK domain
  • A commitment to collaborating on application concepts and feature improvements for Aztec
  • Solid foundational understanding of smart contracts, blockchain applications and Ethereum Layer 2’s

📝 To join our next round of Sandbox Alpha Partners, apply here.

Read more
Aztec Network
Aztec Network
7 Aug
xx min read

Alpha V5 Proving System Vulnerability

Status

Core contributors identified a critical vulnerability affecting the V5 Alpha proving system on 27 July 2026 through internal AI-assisted auditing.

V5 remains Alpha software. Critical findings can arise during this phase, and the audit process exists to identify them before broader deployment. This finding places V5 funds, applications, and contract state at risk.

Treat funds and applications on V5 as exposed to a protocol-level failure until contributors complete incident response work and operators carry out the required network actions.

What we are disclosing

An attacker may be able to exploit a flaw in the current V5 proving system by constructing a proof that passes verification for a transaction the network should reject. If accepted, that transaction could produce a state transition outside the rules V5 intends to enforce.

Contributors cannot determine whether anyone exploited the flaw before this finding. The affected system lacks the information needed to distinguish ordinary accepted transactions from transactions accepted through the flawed proving path. Historical chain activity cannot establish whether exploitation occurred or quantify its impact.

Application safeguards

We expect application teams to prepare safeguards in the coming weeks.

Those safeguards may include changes to application controls, deployment procedures, user flows, and migration plans. We expect each team to assess its contracts and determine which protections fit its architecture and users.

We expect teams planning a V5 deployment to pause that work until contributors publish further guidance. We expect teams with live contracts to review their ability to limit user exposure, isolate affected functionality, and move users to fresh deployments if needed.

We expect applications that maintain administrative or emergency controls to assess whether those controls can reduce user risk during the incident timeframe.

Next steps

Core contributors are working with operators, application teams, and bridge operators as applications add security guards around affected flows.

The findings from this incident will inform the V6 release, including circuit updates that prevent the network from accepting proofs tied to an affected proving system.

V5 launched as Alpha software, with V6 planned for later in 2026. Contributors will publish a security roadmap covering the remaining work and release path.

Known vulnerability status

Reviewers have not identified other high-severity or critical V5 Alpha vulnerabilities at this time.

Internal and external human audits have completed, and contributors continue AI-assisted auditing. Alpha is the period for identifying faults before production deployment.

Community
Community
4 Aug
xx min read

Dark Forest Aztec Game Goes Live

Dark Forest is a real-time strategy game played across a procedurally generated universe where most of the map is hidden. You cannot see rival players, their planets, or their fleets. You only know what you have explored. Everyone shares one universe, and nobody has the full picture.

In most onchain games, every position and every move is public, because the chain is public. Dark Forest used zero-knowledge proofs to break that assumption: players prove their moves are valid without revealing where those moves came from. The result is a game of hidden information running on a public network.

Dark Forest Aztec ports the original Dark Forest 0.6 to Aztec. It keeps the gameplay from the original and rebuilds the privacy layer on Aztec's programmable privacy.

A note before diving in: this is early, experimental software on Aztec Alpha V5. Treat it as an alpha and play accordingly.

The universe you cannot see

You start on a single home planet with almost the entire map dark. To find anything you mine the universe, running a client that explores coordinates and reveals what sits there: unclaimed planets, resources, and eventually the edges of other players' territory.

You are never handed a view of the board. You earn it one region at a time, and everyone else works under the same fog.

What is hidden on Aztec

Your home coordinates and your fleet movements are private state, expressed as first-class private notes on Aztec. Your location and where you send energy stay hidden, enforced in the contracts by zero-knowledge cryptography.

What sits onchain is a set of cryptographic commitments. Instead of storing every planet's full details in the open, the contracts store Poseidon2 hashes of entity state. When you make a move, your client supplies the full state, the contract checks it against the stored hash, applies the change under zero-knowledge constraints, and writes a new hash back. Full game state lives offchain and gets rebuilt from public logs by an indexer, which is what renders your map without exposing every player's position.

So you can prove you made a legal move from a planet you own without revealing where that planet is. Aztec applies the same principle to private payments and private contracts.

How you play

Four actions carry the game.

Explore. Your explorer sits in the bottom left. Set it running and it uncovers the map around you, surfacing planets, resources, and other players.

Send energy. Most planets produce energy. Click and drag from a planet you own toward a target to capture or weaken it.

Route silver. Asteroid fields produce silver. Move it to your planets and spend it on upgrades, or send it to a Spacetime Rip to convert it into score.

Hunt artifacts. Some planets hold artifacts. Your Gear ship discovers them. Once harvested, you deposit them on planets to boost stats.

Four stats drive most decisions.

Energy is the core resource. Planets generate it over time up to a capacity, and you spend it on everything: claiming planets, reinforcing your own, attacking rivals. Two details matter. Moves are taxed, so a flat percentage of a planet's total capacity burns every time you send energy, which discourages small frequent moves. And energy decays over distance, so send it too far and almost nothing arrives. A common rule of thumb is to let a planet fill to about 75%, then send it down to about 25%.

Defense reduces the damage incoming energy does when it lands. Higher-level planets often have lower defense, but they hold much more energy, so they still take more to capture. Defense matters most on front lines.

Range sets how far a planet can send energy. It governs how fast you expand and how efficiently you move energy inside your own empire, since shorter relative distances mean less decay. Good range also lets you strike deep into an opponent's territory.

Speed sets how quickly a move arrives. Usually secondary, though a fast strike can land before a rival reacts, and some playstyles reward capturing many nearby planets quickly.

Planets can also be upgraded with silver and enhanced with artifacts. Space types carry different multipliers, from mild Nebula to punishing Dead Space, so where a planet sits changes how it plays.

How scoring works

There is a scoreboard, and territory alone does not win it. This round scores two activities: discovering artifacts with your Gear ship, and withdrawing silver through Spacetime Rips.

Point values from the in-game help page:

  • Each unit of silver withdrawn: 1
  • Common artifact: 2,000
  • Rare: 10,000
  • Epic: 200,000
  • Legendary: 3,000,000
  • Mythic: 20,000,000

Silver accrues one point at a time. A single Mythic artifact is worth twenty million of them, so artifact hunting decides rounds and silver withdrawal sets your floor.

Silver has two competing uses. Spend it on upgrades and your planets get stronger, extending range and hardening defense. Withdraw it through a Spacetime Rip and it becomes scored points, but it is gone. Every unit is a choice between building the empire and banking points.

Upgrades tend to win early, since a stronger empire reaches more asteroid fields and finds more artifacts. Late in a round that calculation flips, because a planet you never use is worth less than points already scored.

Artifacts do both jobs at once. They score on discovery, and once deposited they boost a planet's stats, which makes the next expedition easier.

Why you explore

Nothing happens until you find something to act on. Your explorer turns dark space into planets you can capture, asteroid fields you can mine, and artifact-bearing planets you can raid. Sitting still means no new energy, no silver, no score.

Exploring also buys information. The map you have uncovered is an advantage nobody else holds. Knowing where high-level planets sit, which asteroid fields are unclaimed, and where space types shift lets you plan further ahead than someone still working through their starting region.

You find other players as a byproduct. There is no player list. You explore outward until your revealed region touches territory someone already owns: a planet in another player's colors, sitting where you were about to expand. Their home coordinates stay private, so you learn something narrow. Someone is here, roughly this direction, holding this much. You infer the rest, and you have no way of knowing whether they found you first.

What happens when you run into someone

You have three broad options.

Stay quiet and keep growing. Nothing forces you to engage. Keep exploring elsewhere, keep routing silver, keep upgrading. Your positions stay private, so silence costs you only time, which is what you want if they are stronger. The risk is that they are doing the same thing faster.

Fortify the border. If the contact sits somewhere you cannot lose, spend energy hardening the planets facing them. Defense is worth most where an attack will actually land. This keeps the option to fight without committing to one.

Attack. Send enough energy to overwhelm the target's defense and the planet becomes yours, along with its production and its position as a staging post. Higher-level planets are the prize and take proportionally more to crack.

Attacking costs more than energy. A move that lands tells your rival where you strike from, and that you are close enough to be worth answering. Retaliation can then come from directions you have not explored, launched from planets you cannot see.

Multiplayer in practice

Everyone plays one shared universe in real time. No turns, no lobbies. Energy regenerates whether you are watching or not, moves stay in flight while you sleep, and rivals expand while you are away from the screen.

Most strategy games let you watch a threat approach. Here you tend to see the consequences: a planet you owned this morning in someone else's colors, an incoming move you notice once it is already close.

That produces a particular kind of paranoia. You are trying to find everyone else while avoiding being found, and every expansion is a strategic bet that the space ahead is empty.

Information becomes tradeable, because it is scarce. Players compare notes, warn each other about aggressive neighbors, and agree who expands where, then break those agreements when the scoreboard makes it worth breaking.

Why it matters beyond the game

A fully onchain game where players cannot see each other's positions is hard to build, and building it well says something about the platform underneath.

Hidden state, private notes, and client-side proving are the same building blocks behind private applications across Aztec. Dark Forest is a way to watch them work.

Getting started

Dark Forest Aztec is playable now as an alpha. Expect a learning curve; the original was famous for it. DFArchon maintains onboarding material and a community for new players. Round One is live. The universe is dark, and everyone else is out there somewhere. Go find them, quietly.

Play Now

Follow the Builders

DFArchon on X

Source and docs

Aztec Network
Aztec Network
22 Jul
xx min read

How Gas Works on Aztec

Gas on Aztec

Gas on Aztec is known as Fee Juice and is used to pay for transaction costs. This is the same as $ETH on Ethereum. Some apps will handle transaction costs for you under the hood, but if you are using a browser extension wallet, you will not be able to send transactions without it. Fee Juice can be obtained by bridging the $AZTEC token on Ethereum to the Aztec Network L2. This means that under the hood, all activity that happens on Aztec is underpinned by the $AZTEC token bridged into the network. Some bridges like Shield (by human.tech) handle this for you, allowing you to allocate a portion of your bridged transaction to convert into Fee Juice and land in your wallet automatically.

Public vs Private Assets

Assets and transactions on the Aztec Network can be either public or private. If you bridge publicly, your tokens will arrive as public, traceable tokens visible to all. Privately bridging, on the other hand, will give you private assets that are visible only to you. These assets can then be sent privately to another user or wallet without ever revealing who you are, what tokens were sent, how many, or who the recipient is.

Public vs Private Gas

Like tokens on the Aztec Network, Fee Juice (gas) can also be public or private. The reason for this is that even if what you are sending is private, the gas you spend to execute that transaction could still be visible if you are using public Fee Juice, potentially revealing transaction patterns and activity. Private Fee Juice keeps your entire transaction footprint hidden. When you send a private transaction, you can use private Fee Juice, and when you send a public transaction, you can use public Fee Juice, which means your transaction costs are always aligned with the type of transaction you're making.

Fee Juice in Apps

Aztec has native fee abstraction, which means apps could let you pay for transactions in any token you want, or cover your fees entirely. Apps like Nyx may choose to cover part or all of a user's transaction costs, or allow you to pay in tokens that are convenient for you. This means you will most likely never see Fee Juice in an app; instead, you'll pay in whatever makes sense for what you're doing, on your terms. Similarly, you might never even see an Aztec wallet at all, because the app itself becomes your interface that you connect to using your MetaMask wallet.

Fee Juice in Browser Wallets

If you're using a browser extension like Azguard, you'll manage Fee Juice directly in your wallet alongside your private and public balances, converting between tokens as needed to cover transaction costs.

When you bridge tokens in, you'll need enough Fee Juice to cover the cost of your first transaction, then you'll need to monitor how much Fee Juice you have available to make transactions. Browser wallets will allow you to send either publicly or privately to other users and will default to using either public or private Fee Juice depending on the type of transaction. Both private Fee Juice and public Fee Juice will appear by default in your token list.

Wrapping up

How you handle Fee Juice depends on where you're transacting: apps can abstract it away entirely and let you pay in any token, while a browser wallet like Azguard puts it in your hands to manage across public and private balances. Match your gas to your transaction, keep private activity private down to the fee, and you move on your terms.

Aztec Network
Aztec Network
21 Jul
xx min read

Introducing Alpha V5

The Aztec Network today activated Alpha V5, a major protocol upgrade passed by token-holder governance and executed onchain. Alpha V5 reduces private-transaction proving times by more than 2x compared to the previous version, lowers the cost of a fully private transaction by roughly 50%, resolves the critical issues found in V4, and sees the first wave of apps go live. Users can now send private transactions and earn yield on Aave simply by connecting their Ethereum wallets on Nyx, bridge from Ethereum to Aztec using Shield or TRAIN, privately collect NFTs on RavenHouse, or play Dark Forest Aztec, a hidden-information strategy game in a universe that lives entirely onchain. 

"Alpha V5 continues Aztec's work at the frontier of client-side proving, with cryptographic breakthroughs that cut proving times by more than half this release," said Zac Williamson, Co-founder, Aztec Foundation. "We believe Aztec is now the fastest system in the world for proving a fully private transaction entirely on a user's own device, and every release moves the industry closer to private transactions at public transaction speeds."

As the only decentralized privacy L2, Aztec is the credibly neutral privacy layer for Ethereum. Aztec allows anyone to write smart contracts that include both private and public aspects – every private transaction is proven on the user's own device, so no operator, sequencer, or intermediary can see the data. The Alpha V5 proving improvements come from cryptographic advances that make this client-side proving faster than any prior release. The network remains in alpha, but with V5 it is ready for teams to begin building and deploying applications.

Performance - 2.5 second fully private transactions 

Making private transactions practical comes down to how quickly a proof can be generated on a user's own device, without offloading that work to a server that would learn what the user is doing. On Alpha V5, proving a private token transfer natively now takes approximately 2.5 seconds on a consumer laptop, down from 5.2 seconds on V4, and about 6.8 seconds in a browser, down from 12.5 seconds. Across every measured transaction flow, client-side proving times improved by approximately 2x compared with V4.

Bench machine: an M2 MacBook (12 cores, throttled to 8). "Native" runs Aztec's C++ proving binary; "WASM" runs the same prover in a browser engine (Node on V8).

Alpha V5 lowers ECDSA signature-verification cost by approximately 2x, speeds up Poseidon2 hashing by approximately 3x, and reduces the protocol circuit gate count by approximately 50% (gate count is the number of individual operations a proving circuit must perform, and it is the main driver of how long a proof takes to generate). Each of these lowers the amount of work a device performs to prove a transaction, and the reduction in gate count in particular compounds across every proof the network generates.

Apps - send, receive, and earn privately on Ethereum

Alpha V5 launches the first wave of apps on a network where privacy is built into the protocol rather than managed by an operator. On other networks that claim privacy, transactions still pass through an operator or node that reads them in plaintext, or depend on a viewing key that a third party holds, so users rely on someone else to protect their data and to decide when it gets disclosed. On Aztec, every private transaction is proven on the user's own device, so the app, the sequencer, and any operator never need to see the underlying data. Nyx is one of these apps, allowing users to privately send transactions and privately earn yield on Aave. 

"On Ethereum, everything you do is public. That's why we built Nyx: a private account governed by your Ethereum wallet", said Nikhil, Co-founder of Nyx. "Now you can send, receive and earn in private. Nyx was the first app live on the Aztec Alpha, and we're excited to expand participation to more users with the added stability of Alpha V5."

Other apps on Alpha V5 include Azguard and Nethermind (wallets), Shield, TRAIN, and RavenHouse (bridges), and the Aztecscan block explorers. Also launching is Dark Forest Aztec, a game where users explore a universe, control planets, manage planetary energy, expand territory, and launch attacks through strategic play with private state and hidden actions.

Dark Forest Aztec private universe-building gameplay

Lower costs, higher security 

Transaction fees on Aztec come from two main sources: the cost of proving a transaction and the cost of verifying the rollup proof on Ethereum. Alpha V5 reduces both. It lowers the network's proving-cost parameter by 50%, and it reduces the L1 gas required to verify a rollup proof by approximately 40%. Because rollup proofs are verified on Ethereum and that cost is shared across all transactions in a batch, the L1 reduction lowers fees for every user, while the lower proving-cost parameter reduces the per-transaction proving fee directly. Together, these bring the average cost of a fully private token transfer to under a $0.05 transaction cost.

Alpha V5 also hardens the network on several fronts. It resolves critical vulnerabilities found in Alpha V4 along with additional bugs discovered since launch. Aztec's bug bounty program on Cantina also drew more than 234 security researchers to participate. The network remains in alpha, and further bugs may surface as usage grows, but each release has closed the issues found in the last and strengthened the protocol against new ones. With the critical V4 issues resolved and these safeguards in place, Alpha V5 is stable enough for teams to begin building and deploying applications.

Availability

Alpha V5 is live now, view the Alpha V5 landing page for a full list of features, performance updates, and live apps to explore. 

About Aztec

Aztec is the only decentralized, privacy-first Layer 2 on Ethereum. Developers write private and public logic in the same smart contract, and private functions are executed and proven on the user's own device, so no operator sees the underlying data. The protocol is upgraded through onchain governance, and the network settles to Ethereum. For more information, visit aztec.network.