Minimal Cairo 1.0 Template

Built with auditless/cairo-template

A minimal template for building smart contracts with Cairo 1.0 using the alexandria project defaults.

How it works

• No submodules, forks or other heavy machinery
• Uses protostar toolchain for running tests
• Built as a Scarb package for reusability and uses Scarb dependencies for libraries
• Has reproducible builds using GitHub Actions
• Uses Scarb scripts natively for custom commands
• Includes advanced debugging views like the Sierra intermediate representation

Installing dependencies

Step 1: Install the Cairo package manager Scarb

Follow the installation guide in Scarb's documentation.

Step 2: Install the Protostar toolchain

Follow the installation guide in Protostar's Repository.

Step 3: Install Cairo 1.0 (guide by Abdel)

NOTE: By installing Scarb, you already have an accompanying Cairo 1.0 version which can be viewed by running $ scarb --version. This installation step is included to allow you maintain an independent version of Cairo. This step will also prove useful when setting up the language server in Step 5.

If you are on an x86 Linux system and able to use the release binary, you can download Cairo here https://github.com/starkware-libs/cairo/releases.

For everyone, else, we recommend compiling Cairo from source like so:

# Install stable Rust
$ rustup override set stable && rustup update

# Clone the Cairo compiler in $HOME/Bin
$ cd ~/Bin && git clone git@github.com:starkware-libs/cairo.git && cd cairo

# OPTIONAL/RECOMMENDED: If you want to install a specific version of the compiler
# Fetch all tags (versions)
git fetch --all --tags
# View tags (you can also do this in the cairo compiler repository)
git describe --tags `git rev-list --tags`
# Checkout the version you want
git checkout tags/v1.0.0-alpha.6

# Generate release binaries
$ cargo build --all --release

NOTE: Keeping Cairo up to date

Now that your Cairo compiler is in a cloned repository, all you will need to do is pull the latest changes and rebuild as follows:

$ cd ~/Bin/cairo && git fetch && git pull && cargo build --all --release

Step 4: Add Cairo 1.0 executables to your path

export PATH="$HOME/Bin/cairo/target/release:$PATH"

NOTE: If installing from a Linux binary, adapt the destination path accordingly.

This will make available several binaries. The one we use is called cairo-test.

Step 5: Setup Language Server

VS Code Extension

• Disable previous Cairo 0.x extension
• Install the Cairo 1 extension for proper syntax highlighting and code navigation. Just follow the steps indicated here.

Cairo Language Server

The Cairo Language Server now comes bundled with the Scarb package manger distribution. You can make sure it is available in your system by running $ scarb commands. The output should include a line starting with cairo-language-server.

How to use this template

First you will need to clone the repository or click the Use this template button at the top of the page to create a new repository based on the template.

Next, you will want to update the configuration file with the name of your project:

└── .Scarb.toml

Also, if you're using a different protostar version, you'll want to update the version in the configuration file as well

└── .protostar.toml

Working with your project

The Cairo template currently supports building and testing contracts.

Build

Build the contracts.

$ scarb build

Test

Run the tests in src/test:

$ scarb run test

Format

Format the Cairo source code (using Scarb):

$ scarb fmt

Sierra and Casm (advanced)

The Sierra output of your cairo code is automatically built by scarb when you run $ scarb build.

To change this behaviour, add the following code to the [lib] section of your Scarb.toml configuration file

    [lib]
    sierra = false

Similarly, to generate casm (Cairo assembly), add the following code to the [lib] section of your Scarb.toml configuration file

    [lib]
    casm = true

Thanks to

• The alexandria team for coming up with this configuration and especially Abdel for helping me with Cairo 1.0 installation
• Paul Berg and the foundry-template project which served as inspiration
• Last but not least, the StarkWare team for building the first smart contract language that is a joy to use

Other templates

• ArgentX template is built as a fork of the compiler
• Eni's cairo1-template uses git submodules for installation
• Shramee's Starklings use the cairo1 crates as libraries and builds its own framework

License

MIT © Auditless Limited