Release process

5 min

Before releasing a new version of Garage, our code pass through a succession of checks and transformations. We define them as our release process.

Trigger and classify a release

While we run some tests on every commits, we do not make a release for all of them.

A release can be triggered manually by "promoting" a successful build. Otherwise, every night, a release build is triggered on the main branch.

If the build is from a tag following the regex: v[0-9]+\.[0-9]+\.[0-9]+, it will be listed as stable. If it is a tag but with a different format, it will be listed as Extra. Otherwise, if it is a commit, it will be listed as development. This logic is defined in nix/build_index.nix.


For each commit, we first pass the code to a formatter (rustfmt) and a linter (clippy). Then we try to build it in debug mode and run both unit tests and our integration tests.

Additionnaly, when releasing, our integration tests are run on the release build for amd64 and i686.

Generated Artifacts

We generate the following binary artifacts for now:

  • architecture: amd64, i686, aarch64, armv6
  • os: linux
  • format: static binary, docker container

Additionnaly we also build two web pages and one JSON document:

We publish the static binaries on our own garage cluster (you can access them through the releases page) and the docker containers on Docker Hub.


We automated our release process with Nix and Woodpecker to make it more reliable. Here we describe how we have done in case you want to debug or improve it.

Caching build steps

To speed up the CI, we use the caching feature provided by Nix.

You can benefit from it by using our provided nix.conf as recommended or by simply adding the following lines to your file:

substituters =
trusted-public-keys =

Sending to the cache is done through nix copy, for example:

nix copy --to 's3://nix?' result

The signing key possessed by the Garage maintainers is required to update the Nix cache.

The previous command will only send the built package and not its dependencies. In the case of our CI pipeline, we want to cache all intermediate build steps as well. This can be done using this quite involved command (here as an example for the pkgs.amd64.relase package):

nix copy -j8 \
    --to 's3://nix?' \
    $(nix path-info pkgs.amd64.release --file default.nix --derivation --recursive | sed 's/\.drv$/.drv^*/')

This command will simultaneously build all of the required Nix paths (using at most 8 parallel Nix builder jobs) and send the resulting objects to the cache.

This can be run for all the Garage packages we build using the following command:

source ~/.awsrc
nix-shell --attr cache --run 'refresh_cache'

We don't automate this step at each CI build, as there is currently no automatic garbage collection of the cache. This means we should also monitor the cache's size; if it ever becomes too big we can erase it with:

mc rm --recursive --force 'garage/nix/'

Publishing Garage

We defined our publishing logic in Nix, mostly as shell hooks. You can inspect them in shell.nix to see exactly how. Here, we will give a quick explanation on how to use them to manually publish a release.

Supposing you just have built garage as follow:

nix-build --arg release true

To publish a static binary in result/bin on garagehq, run:

export AWS_ACCESS_KEY_ID=xxx
export DRONE_TAG=handcrafted-1.0.0 # or DRONE_COMMIT
export TARGET=x86_64-unknown-linux-musl

nix-shell --run to_s3

To create and publish a docker container, run:

export DOCKER_AUTH='{ "auths": { "": { "auth": "xxxx" }}}'
export DOCKER_PLATFORM='linux/amd64' # check GOARCH and GOOS from
export CONTAINER_NAME='me/amd64_garage'
export CONTAINER_TAG='handcrafted-1.0.0'

nix-shell --run to_docker

To rebuild the release page, run:

export AWS_ACCESS_KEY_ID=xxx

nix-shell --run refresh_index

If you want to compile for different architectures, you will need to repeat all these commands for each architecture.

In practice, and except for debugging, you will never directly run these commands. Release is handled by Woodpecker.

Drone (obsolete)

Our instance is available at
You need an account on to use it.

Drone CLI - Drone has a CLI tool to interact with. It can be downloaded from its Github release page.

To communicate with our instance, you must setup some environment variables. You can get them from your Account Settings.

To make drone easier to use, you could create a ~/.dronerc that you could source each time you want to use it.

export DRONE_TOKEN=xxx
drone info

The CLI tool is very self-discoverable, just append --help to each subcommands. Start with:

drone --help

.drone.yml - The builds steps are defined in .drone.yml.
You can not edit this file without resigning it.

To sign it, you must be a maintainer and then run:

drone sign --save Deuxfleurs/garage

Looking at the file, you will see that most of the commands are nix-shell and nix-build commands with various parameters.