Installation
This page will guide you through the steps needed to prepare a computer for Substrate development. Since Substrate is built with the Rust programming language, the first thing you will need to do is prepare the computer for Rust development - these steps will vary based on the computer's operating system. Once Rust is configured, you will use its toolchains to interact with Rust projects; the commands for Rust's toolchains will be the same for all supported, Unix-based operating systems.
Unix-Based Operating Systems
Substrate development is easiest on Unix-based operating systems like macOS or Linux. The examples in the Substrate Tutorials and Recipes use Unix-style terminals to demonstrate how to interact with Substrate from the command line.
macOS
Open the Terminal application and execute the following commands:
# Install Homebrew if necessary https://brew.sh/
/bin/bash -c "$(curl -fsSL https://raw.githubusercontent.com/Homebrew/install/master/install.sh)"
# Make sure Homebrew is up-to-date, install openssl and cmake
brew update
brew install openssl cmake
Ubuntu/Debian
Use a terminal shell to execute the following commands:
sudo apt update
# May prompt for location information
sudo apt install -y cmake pkg-config libssl-dev git build-essential clang libclang-dev curl
Arch Linux
Run these commands from a terminal:
pacman -Syu --needed --noconfirm cmake gcc openssl-1.0 pkgconf git clang
export OPENSSL_LIB_DIR="/usr/lib/openssl-1.0"
export OPENSSL_INCLUDE_DIR="/usr/include/openssl-1.0"
Windows
Please refer to the separate guide for Windows users.
Rust Developer Environment
This guide uses rustup to help manage the Rust toolchain. First install and
configure rustup:
# Install
curl https://sh.rustup.rs -sSf | sh
# Configure
source ~/.cargo/env
Configure the Rust toolchain to default to the latest stable version:
rustup default stable
WebAssembly Compilation
Substrate uses WebAssembly (Wasm) to produce portable blockchain
runtimes. You will need to configure your Rust compiler to use
nightly builds to allow you to
compile Substrate runtime code to the Wasm target.
Rust Nightly Toolchain
Developers building with Substrate should use a specific Rust nightly version that is known to be compatible with the version of Substrate they are using; this version will vary from project to project and different projects may use different mechanisms to communicate this version to developers. For instance, the Polkadot client specifies this information in its release notes. The Substrate Node Template uses an init script and Makefile to specify the Rust nightly version and encapsulate the following steps. Use Rustup to install the correct nightly:
rustup install nightly-<yyyy-MM-dd>
Wasm Toolchain
Now, configure the nightly version to work with the Wasm compilation target:
rustup target add wasm32-unknown-unknown --toolchain nightly-<yyyy-MM-dd>
Specifying Nightly Version
Use the WASM_BUILD_TOOLCHAIN environment variable to specify the Rust nightly version a Substrate
project should use for Wasm compilation:
WASM_BUILD_TOOLCHAIN=nightly-<yyyy-MM-dd> cargo build --release
Note that this only builds the runtime with the specified nightly. The rest of project will be compiled with the default toolchain, i.e. the latest installed stable toolchain.
Latest Nightly for Substrate master
Developers that are building Substrate itself should always use the latest bug-free versions of Rust stable and nightly. This is because the Substrate codebase follows the tip of Rust nightly, which means that changes in Substrate often depend on upstream changes in the Rust nightly compiler. To ensure your Rust compiler is always up to date, you should run:
rustup update
rustup update nightly
rustup target add wasm32-unknown-unknown --toolchain nightly
It may be necessary to occasionally rerun rustup update if a change in the upstream Substrate
codebase depends on a new feature of the Rust compiler.
Downgrading Rust Nightly
If your computer is configured to use the latest Rust nightly and you would like to downgrade to a specific nightly version, follow these steps:
rustup uninstall nightly
rustup install nightly-<yyyy-MM-dd>
rustup target add wasm32-unknown-unknown --toolchain nightly-<yyyy-MM-dd>
Test Your Set-Up
The best way to ensure that you have successfully prepared a computer for Substrate development is to follow the steps in our first tutorial, Create Your First Substrate Chain.