Clarinet

Clarinet is the fastest way to build, test, and deploy smart contracts on the Stacks blockchain. It gives you a local devnet, REPL, testing framework, and debugging tools to ship high-quality Clarity code with confidence.

• 🧑‍💻 Leverage a powerful CLI Create new projects, manage your smart contracts and their dependencies using clarinet requirements, and interact with your code through the built-in REPL.

• 🧪 Write unit tests with the SDK Use the Clarinet SDK to write unit tests in a familiar JS environment and validate contract behavior.

• 🛠️ Run a private blockchain environment Spin up a local devnet with nodes, miners, and APIs so you can test and integrate your code.

• 🔍 VSCode extension: Linter, step by step debugger, helps writing smart contracts (autocompletion, documentation etc)

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Documentation

• Clarinet CLI
• Clarinet JS SDK and testing framework

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Quickstart

# Install Clarinet
brew install clarinet

To check out more installation methods, click here

# Create a new project
clarinet new hello-world
cd hello-world

# Create a new contract
clarinet contract new counter

;; Add this to the `contracts/counter.clar`

(define-map counters principal uint)

(define-public (count-up)
  (ok (map-set counters tx-sender (+ (get-count tx-sender) u1)))
)

(define-read-only (get-count (who principal))
  (default-to u0 (map-get? counters who))
)

# Then test it out

# Check the contract
clarinet check

# Launch the REPL
clarinet console

# Inside the console
(contract-call? .counter count-up)
(contract-call? .counter get-count tx-sender)

Contributing

Contributions are welcome and appreciated. The following sections provide information on how you can contribute to Clarinet.

Prerequisites

Before contributing to Clarinet, you need the following tools.
Although it will work with older versions, the team always tries to keep up with the latest versions of Rust and Node.js (LTS) tooling.

• Rust (>=1.89.0)
• Cargo (>=1.89.0)
• Node (>=v24.4.1)
• NPM (>=11.5.2)

Guide

This repo follows the Conventional Commit specification when writing commit messages.

Note: These conventions are helpful for any commit message, but all PR end up being merged with "squash and merge", giving an other chance to refine the commit messages.

To start contributing, fork this repo and open a new branc:

1. Fork this repo and clone the fork locally.
2. Create a new branch

   git checkout -b <my-branch>

Contributing to the CLI

1. After making your changes, ensure the following:
   • cargo build runs successfully.
   • cargo tst runs successfully.
     • cargo tst is an alias declared in ./cargo/config, it runs cargo-nextest
   • You have formatted your code with cargo fmt-stacks
   • All functional tests in the examples directory pass.

     for testdir in $(ls examples); do
         pushd examples/${testdir}
             ../../target/debug/clarinet check .
         popd
     done

2. Submit a pull request against the main branch for review.

Contributing to the JS SDK

For VSCode users, we recommend opening the following workspace ./components/clarinet-sdk/clarinet-sdk.code-workspace. It's set up so that rust-analyzer uses the Wasm target.

The SDK is divided between the Rust lib compiled to Wasm ./components/clarinet-sdk-wasm and a TS wrapper around it: ./components/clarinet-sdk-wasm.

1. Compile the Wasm package with npm run build:sdk-wasm
2. Compile the SDK with npm run build:sdk
3. Test with npm test

Learn more in the SDK Readme.md.

Code of Conduct

Please read our Code of conduct since we expect project participants to adhere to it.

Community

Join our community and stay connected with the latest updates and discussions:

• Join our Discord community chat to engage with other users, ask questions, and participate in discussions.
• Visit hiro.so for updates and subscribing to the mailing list.
• Follow Hiro on X.