Aztec

Aztec is an Ethereum Layer 2 network designed to support smart contracts with both private and public data and execution. Its architecture uses zero-knowledge proofs and client-side private execution to enable privacy-preserving applications while settling transaction proofs to Ethereum. ^[6]

Overview

Aztec is a privacy-focused Layer 2 network on Ethereum that supports smart contracts with both private and public state and execution. Its architecture separates private and public computation: private functions run on users’ devices through a Private Execution Environment (PXE), where zero-knowledge proofs are generated, while public functions run on the Aztec Virtual Machine (AVM) across the network. Private state uses a UTXO-based model with notes, commitments, and nullifiers, while public state follows an account-based model similar to Ethereum. Transactions combine private proofs and public state updates before being rolled up and submitted to Ethereum for verification.

The Aztec stack consists of Noir, the zero-knowledge programming language used to write private applications; the Aztec.nr framework for developing smart contracts that combine private and public functions; the Aztec Network, which coordinates execution, sequencing, and proving; and Ethereum, where rollup proofs and state updates are settled. The network also uses account abstraction, allowing accounts to be implemented as smart contracts with customizable authorization, key management, and transaction fee mechanisms. Its privacy model is designed to cover data, identity, and computation, while its permissionless sequencer-and-prover architecture supports decentralized participation in the network. ^[3] ^[5]

Features

Noir

Noir is an open-source programming language with Rust-like syntax designed for developing zero-knowledge applications and privacy-preserving programs. It abstracts much of the underlying cryptographic complexity, allowing developers to write zero-knowledge programs without requiring extensive knowledge of cryptography. Privacy is the default in Noir, with variables and functions treated as private and executed locally unless developers explicitly designate elements as public. Noir programs compile into an intermediate representation called ACIR, which can be processed by different zero-knowledge proving backends to generate proofs that verify program execution without revealing private inputs. The language can be used for applications such as proving attributes or ownership without disclosing underlying information, and its programs can operate independently of Aztec. For applications that require private state to be stored and managed onchain, Noir can be used with the Aztec smart contract framework to combine private and public state. ^[4]

Alpha Network

The Aztec Alpha Network is a privacy-focused Layer 2 network on Ethereum that provides a full execution environment for private smart contracts. It allows developers to determine which aspects of an application remain public or private across three areas: data, identity, and computation. Private transactions and contract logic are executed locally on users’ devices, where zero-knowledge proofs are generated and submitted to the network for validation, whereas public components are executed by sequencers. The resulting proofs are settled on Ethereum, and the network is designed as a decentralized rollup rather than being operated directly by Aztec Labs or the Aztec Foundation.

The Alpha Network supports composable private and public smart contracts, allowing contracts to interact while preserving privacy across calls. Applications are developed using Noir, a Rust-like programming language, and the Aztec.nr framework, with private functions executed locally and public functions processed by the network. Its privacy capabilities cover private data for transactions and financial assets, private identity for selective disclosure and compliance applications, and private computation for applications requiring confidential execution. Alpha represents an early version of the network, with known vulnerabilities and planned upgrades intended to improve security as it progresses toward later development stages. ^[2]

Token

AZTEC is the native token of the Aztec Network and is used across transaction fees, network staking, governance, and participant incentives. It can be bridged from Ethereum and used to pay gas fees, while network operators can stake AZTEC to become sequencers who propose and validate blocks. Staked tokens also provide voting rights on protocol upgrades, with governance conducted by participating sequencers. The token is additionally distributed through network emissions to sequencers and provers for proposing and proving finalized blocks, respectively. ^[7]