The Leo Programming Language

Leo is a functional, statically-typed programming language built for writing private applications. ## Table of Contents * [1. Overview](#1-overview) * [2. Build Guide](#2-build-guide) * [2.1 Install Rust](#21-install-rust) * [2.2a Build from Crates.io](#22a-build-from-cratesio) * [2.2b Build from Source Code](#22b-build-from-source-code) * [3. Quick Start](#3-quick-start) * [4. Documentation](#4-documentation) * [5. Contributing](#5-contributing) * [6. License](#6-license) ## 1. Overview Welcome to the Leo programming language. Leo provides a high-level language that abstracts low-level cryptographic concepts and makes it easy to integrate private applications into your stack. Leo compiles to circuits making zero-knowledge proofs practical. The syntax of Leo is influenced by traditional programming languages like JavaScript, Scala, and Rust, with a strong emphasis on readability and ease-of-use. Leo offers developers with tools to sanity check circuits including unit tests, integration tests, and console functions. Leo is one part of a greater ecosystem for building private applications on [Aleo](https://aleo.org/). If your goal is to build a user experience on the web that is both truly personal and truly private, then we recommend downloading the [Aleo Studio IDE](https://aleo.studio/) and checking out the [Aleo Package Manager](https://aleo.pm/). ## 2. Build Guide ### 2.1 Install Rust We recommend installing Rust using [rustup](https://www.rustup.rs/). You can install `rustup` as follows: - macOS or Linux: ```bash curl --proto '=https' --tlsv1.2 -sSf https://sh.rustup.rs | sh ``` - Windows (64-bit): Download the [Windows 64-bit executable](https://win.rustup.rs/x86_64) and follow the on-screen instructions. - Windows (32-bit): Download the [Windows 32-bit executable](https://win.rustup.rs/i686) and follow the on-screen instructions. ### 2.2a Build from Crates.io We recommend installing Leo this way. In your terminal, run: ```bash cargo install leo-lang ``` Now to use Leo, in your terminal, run: ```bash leo ``` ### 2.2b Build from Source Code Alternatively, you can install Leo by building from the source code as follows: ```bash # Download the source code git clone https://github.com/AleoHQ/leo cd leo # Build in release mode $ cargo build --release ``` This will generate an executable under the `./target/release` directory. To run Leo, run the following command: ```bash ./target/release/leo ``` ## 3. Quick Start Use the Leo CLI to create a new project ```bash # create a new `hello-world` Leo project leo new hello-world cd hello-world # build & setup & prove & verify leo run ``` The `leo new` command creates a new Leo project with a given name. The `leo run` command will compile the main program, generate keys for a trusted setup, fetch inputs, generate a proof and verify it. Congratulations! You've just run your first Leo program. ## 4. Documentation * [Hello World - Next Steps](https://developer.aleo.org/developer/getting_started/hello_world) * [Leo Language Documentation](https://developer.aleo.org/developer/language/layout) * [Leo ABNF Grammar](./grammar/README.md) * [Leo CLI Documentation](https://developer.aleo.org/developer/cli/new) * [Homepage](https://developer.aleo.org/developer/getting_started/overview) ## 5. Contributing Please see our guidelines in the [developer documentation](https://developer.aleo.org/developer/additional_material/contributing) Thank you for helping make Leo better! ## 6. License [![License: GPL v3](https://img.shields.io/badge/License-GPLv3-blue.svg)](./LICENSE.md)