garage/doc/book/src/development/devenv.md

Setup your development environment

Depending on your tastes, you can bootstrap your development environment in a traditional Rust way or through Nix.

The Nix way

Nix is a generic package manager we use to precisely define our development environment. Instructions on how to install it are given on their Download page.

Check that your installation is working by running the following commands:

nix-shell --version
nix-build --version
nix-env   --version

Now, you can clone our git repository (run nix-env -iA git if you do not have git yet):

git clone https://git.deuxfleurs.fr/Deuxfleurs/garage
cd garage

Optionnaly, you can use our nix.conf file to speed up compilations:

sudo mkdir -p /etc/nix
sudo cp nix/nix.conf /etc/nix/nix.conf
sudo killall nix-daemon

Now you can enter our nix-shell, all the required packages will be downloaded but they will not pollute your environment outside of the shell:

nix-shell

You can use the traditionnal Rust development workflow:

cargo build  # compile the project
cargo run    # execute the project
cargo test   # run the tests
cargo fmt    # format the project, run it before any commit!
cargo clippy # run the linter, run it before any commit!

You can build the project with Nix by running:

nix-build

You can parallelize the build (if you use our nix.conf file, it is already automatically done). To use all your cores when building a derivation use -j, and to build multiple derivations at once use --max-jobs. The special value auto will be replaced by the number of cores of your computer. An example:

nix-build -j $(nproc) --max-jobs auto

Our build has multiple parameters you might want to set:

• release build with release optimisations instead of debug
• target allows for cross compilation
• compileMode can be set to test or bench to build a unit test runner
• git_version to inject the hash to display when running garage stats

An example:

nix-build \
  --arg release true \
  --argstr target x86_64-unknown-linux-musl \
  --argstr compileMode build \
  --git_version $(git rev-parse HEAD)

The result is located in result/bin. You can pass arguments to cross compile: check .drone.yml for examples.

If you modify a Cargo.toml or regenerate any Cargo.lock, you must run cargo2nix:

cargo2nix -f

Many tools like rclone, mc (minio-client), or aws (awscliv2) will be available in your environment and will be useful to test Garage.

This is the recommended method.

The Rust way

You need a Rust distribution installed on your computer. The most simple way is to install it from rustup. Please avoid using your package manager to install Rust as some tools might be outdated or missing.

Now, check your Rust distribution works by running the following commands:

rustc --version
cargo --version
rustfmt --version
clippy-driver --version

Now, you need to clone our git repository (how to install git):

git clone https://git.deuxfleurs.fr/Deuxfleurs/garage
cd garage

You can now use the following commands:

cargo build  # compile the project
cargo run    # execute the project
cargo test   # run the tests
cargo fmt    # format the project, run it before any commit!
cargo clippy # run the linter, run it before any commit!

This is specific to our project, but you will need one last tool, cargo2nix. To install it, run:

cargo install --git https://github.com/superboum/cargo2nix --branch main cargo2nix

You must use it every time you modify a Cargo.toml or regenerate a Cargo.lock file as follow:

cargo build  # Rebuild Cargo.lock if needed
cargo2nix -f

It will output a Cargo.nix file which is a specific Cargo.lock file dedicated to Nix that is required by our CI which means you must include it in your commits.

Later, to use our scripts and integration tests, you might need additional tools. These tools are listed at the end of the shell.nix package in the nativeBuildInputs part. It is up to you to find a way to install the ones you need on your computer.

A global drawback of this method is that it is up to you to adapt your environment to the one defined in the Nix files.