Contract Structure

A contract is a collection of persistent state variables and functions which may manipulate these variables. Functions and state variables within a contract's scope are said to belong to that contract.

A contract can only access and modify its own state. If a contract wishes to access or modify another contract's state, it must make a call to an external function of the other contract. For anything to happen on the Aztec network, an external function of a contract needs to be called.

Contract

A contract is declared using the #[aztec] attribute and the contract keyword. By convention, contracts are named in PascalCase.

setup

use dep::aztec::macros::aztec;

#[aztec]
pub contract Counter {

^{_{Source code: docs/examples/contracts/counter_contract/src/main.nr#L1-L6}}

A note for vanilla Noir devs

There is no main() function within a Noir contract scope. More than one function can be an entrypoint.

Directory structure

Here's a common layout for a basic Aztec.nr Contract project:

layout of an aztec contract project

─── my_aztec_contract_project
       ├── src
       │     └── main.nr       <-- your contract
       └── Nargo.toml          <-- package and dependency management

See the vanilla Noir docs for more info on packages.

Next steps

• Define functions - Learn about private, public, and utility functions
• Define storage - Work with persistent state variables
• Compile your contract - Build your contract artifact