Aztec

• Aztec is an Ethereum Layer 2 offering programmable privacy through zero-knowledge proofs.

• Contracts written in its Noir language can keep state and transaction details encrypted while still being verifiable.

• AZTEC is used for staking by sequencers and provers, governance and Layer 2 gas.

• Emissions reward block proposers and validators, weighted toward proposers.

• Staked by sequencers and provers securing the network.

• An adaptive fee system adjusts gas pricing with demand.

Pros:

• Client-side proving means sensitive computation happens on the user's device, never reaching a node.

• Noir is a purpose-built language for private contracts rather than a privacy layer bolted onto Solidity.

• Years of published cryptographic research behind the implementation.

Cons:

• Privacy protocols attract regulatory attention, and several privacy tools have faced enforcement action.

• Client-side proving is computationally demanding for users on ordinary hardware.

• Very long development timeline before mainnet.

• Exposure to programmable privacy on Ethereum with substantial research behind it.

• Private smart contracts are a capability nothing else on Ethereum currently offers.

• Weigh the regulatory trajectory for privacy infrastructure, which is the dominant risk.

• Smart contracts where both state and execution stay encrypted, rather than privacy limited to transferring one asset.

• Every Ethereum transaction is public, so any business use exposes counterparties, amounts and strategy.

• Encrypted contract state makes confidential applications possible, at a heavy proving cost.

• Founded by Zac Williamson and Joe Andrews.

• Backed by a16z crypto, Paradigm and Variant.

• Aztec held a public token sale from 2 to 6 December 2025 using Uniswap's Continuous Clearing Auction, selling 14.95% of total supply and raising about $59 million at a final fully diluted valuation of about $557 million.

• Privacy infrastructure faces active regulatory and enforcement pressure globally.

• Client-side proving is demanding on consumer hardware.

• Long development timeline with continued delivery risk.

• Adoption requires developers to learn a new language.

Aztec's research argues that privacy on Ethereum has been treated as an asset-level feature — mixing one token, shielding one transfer — when the actual requirement is privacy at the level of program state. A business using a public chain exposes not just amounts but counterparties, positions and logic, and no amount of transaction mixing fixes that. Aztec's approach splits execution: private functions are proved on the user's own device so the inputs never leave it, while public functions run on the network as normal, and the two compose within a single contract. The papers are direct that this shifts substantial computational cost onto the user, and treat that as the price of the guarantee rather than something to be engineered away.