Anchor is a framework providing several convenient developer tools for writing Solana programs (sometimes called ‘smart contracts’).

• Rust eDSL for writing Solana programs
• IDL specification
• TypeScript package for generating clients from IDL
• CLI and workspace management for developing complete applications

Anchor is the most popular framework for Solana programs.

[!NOTE] If you’re familiar with developing in Ethereum’s Solidity, Truffle, web3.js, then using Anchor will be familiar. Although the DSL syntax and semantics are targeted at Solana, the high level flow of writing RPC request handlers, emitting an IDL, and generating clients from IDL is the same.

Getting Started

For a quickstart guide and in depth tutorials, see the Anchor book and the Anchor documentation.

To jump straight to examples, go here. For the latest Rust and TypeScript API documentation, see docs.rs and the typedoc.

Installation

The recommended way to install the Anchor CLI is with the Anchor Version Manager (AVM).

curl -sSfL https://raw.githubusercontent.com/solana-foundation/anchor/master/avm/install | sh

The installer downloads the latest nightly AVM and Anchor CLI binaries, enables the nightly channel, and links the avm and anchor commands into ~/.cargo/bin when possible. After that, anchor will use the latest cached nightly build and periodically check for updates.

If you already have AVM installed, you can enable the nightly channel directly:

avm nightly

To leave nightly mode and return to normal AVM version resolution, run:

avm nightly --disable

Packages

Package	Description	Version	Docs
anchor-lang	Rust primitives for writing programs on Solana
anchor-spl	CPI clients for SPL programs on Solana
anchor-client	Rust client for Anchor programs
@anchor-lang/core	TypeScript client for Anchor programs
@anchor-lang/cli	CLI to support building and managing an Anchor workspace

Examples

Here’s a counter program, where only the designated authority can increment the count.

use anchor_lang::prelude::*;

declare_id!("Fg6PaFpoGXkYsidMpWTK6W2BeZ7FEfcYkg476zPFsLnS");

#[program]
mod counter {
    use super::*;

    pub fn initialize(ctx: Context<Initialize>, start: u64) -> Result<()> {
        let counter = &mut ctx.accounts.counter;
        counter.authority = *ctx.accounts.authority.key;
        counter.count = start;
        Ok(())
    }

    pub fn increment(ctx: Context<Increment>) -> Result<()> {
        let counter = &mut ctx.accounts.counter;
        counter.count += 1;
        Ok(())
    }
}

#[derive(Accounts)]
pub struct Initialize<'info> {
    #[account(init, payer = authority, space = 48)]
    pub counter: Account<'info, Counter>,
    pub authority: Signer<'info>,
    pub system_program: Program<'info, System>,
}

#[derive(Accounts)]
pub struct Increment<'info> {
    #[account(mut, has_one = authority)]
    pub counter: Account<'info, Counter>,
    pub authority: Signer<'info>,
}

#[account]
pub struct Counter {
    pub authority: Pubkey,
    pub count: u64,
}

For more, see the examples and tests directories.

Fuzzing

anchor fuzz integrates Crucible for coverage-guided program fuzzing. See the fuzzing docs or the Crucible docs.

# scaffold a fuzz harness
anchor fuzz init program_name

# run a fuzz test
anchor fuzz run program_name test_name --release

License

Anchor is licensed under Apache 2.0.

Unless you explicitly state otherwise, any contribution intentionally submitted for inclusion in Anchor by you, as defined in the Apache-2.0 license, shall be licensed as above, without any additional terms or conditions.

This code is provided as-is, without warranties or liability.

Contribution

Thank you for your interest in contributing to Anchor! Please see the CONTRIBUTING.md to learn how.

Thanks ❤️