This page will guide you through the 3 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.
Please refer to the separate guide for native Windows development.
1.b 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.
Use a terminal shell to execute the following commands:
sudo apt update # May prompt for location information sudo apt install -y git clang curl libssl-dev
Run these commands from a terminal:
pacman -Syu --needed --noconfirm 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"
Run these commands from a terminal:
sudo dnf update sudo dnf install clang curl git openssl-devel
NOTE: The Apple M1 ARM system on a chip is not very well supported yet by rust, and thus you very likely will run into build errors stemming from this. It is best, for the near term, to avoid using M1s for Substrate development. If you do decide to give it a try despite this, see this community guide for details on extra configuration steps to get things working.
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 brew update brew install openssl
2. Rust Developer Environment
This guide uses
rustup to help manage the Rust toolchain. First install and
# 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
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.
There are upstream issues in Rust that need to be resolved before all of Substrate can use the stable Rust toolchain - this is our tracking issue if you are curious as to why and how this may be resolved.
Latest Nightly for Substrate
Developers who 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 updateif a change in the upstream Substrate codebase depends on a new feature of the Rust compiler. When you do this, both your nightly and stable toolchains will be pulled to the most recent release, and for nightly, it is generally not expected to compile WASM without error (although it very often does). be sure to specify your nightly version if you get WASM build errors from
rustupand downgrade nightly as needed.
Rust Nightly Toolchain
If you want to guarantee that your build works on your computer as you update Rust and other dependencies, you 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.
# Specify the specific nightly toolchain in the date below: rustup install nightly-<yyyy-MM-dd>
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
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 your default toolchain, i.e. the latest installed stable toolchain.
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>
Rust Configuration Check
To see what Rust toolchain you are presently using, run:
Default host: x86_64-unknown-linux-gnu rustup home: /home/user/.rustup installed toolchains -------------------- stable-x86_64-unknown-linux-gnu (default) nightly-2020-10-06-x86_64-unknown-linux-gnu nightly-x86_64-unknown-linux-gnu installed targets for active toolchain -------------------------------------- wasm32-unknown-unknown x86_64-unknown-linux-gnu active toolchain ---------------- stable-x86_64-unknown-linux-gnu (default) rustc 1.50.0 (cb75ad5db 2021-02-10)
As you can see in the Ubuntu based example above, the default toolchain is stable, and the
nightly-x86_64-unknown-linux-gnu toolchain as well as
wasm32-unknown-unknown target is installed.
You also see that
nightly-2020-10-06-x86_64-unknown-linux-gnu is installed, but is not used unless explicitly defined as illustrated in the specify your nightly version
3. Test Your Set-Up
Now The best way to ensure that you have successfully prepared a computer for Substrate development is to follow the steps in our first tutorial: