GARM enables you to create and automatically maintain pools of [self-hosted GitHub runners](https://docs.github.com/en/actions/hosting-your-own-runners/about-self-hosted-runners), with auto-scaling that can be used inside your github workflow runs.
The goal of ```GARM``` is to be simple to set up, simple to configure and simple to use. It is a single binary that can run on any GNU/Linux machine without any other requirements other than the providers it creates the runners in. It is intended to be easy to deploy in any environment and can create runners in any system you can write a provider for. There is no complicated setup process and no extremely complex concepts to understand. Once set up, it's meant to stay out of your way.
GARM supports creating pools on either GitHub itself or on your own deployment of [GitHub Enterprise Server](https://docs.github.com/en/enterprise-server@3.5/admin/overview/about-github-enterprise-server). For instructions on how to use ```GARM``` with GHE, see the [credentials](/doc/github_credentials.md) section of the documentation.
Through the use of providers, `GARM` can create runners in a variety of environments using the same `GARM` instance. Want to create pools of runners in your OpenStack cloud, your Azure cloud and your Kubernetes cluster? No problem! Just install the appropriate providers, configure them in `GARM` and you're good to go. Create zero-runner pools for instances with high costs (large VMs, GPU enabled instances, etc) and have them spin up on demand, or create large pools of k8s backed runners that can be used for your CI/CD pipelines at a moment's notice. You can mix them up and create pools in any combination of providers or resource allocations you want.
Whether you're running into issues or just want to drop by and say "hi", feel free to [join us on slack](https://communityinviter.com/apps/garm-hq/garm).
Check out the [quickstart](/doc/quickstart.md) document for instructions on how to install ```GARM```. If you'd like to build from source, check out the [building from source](/doc/building_from_source.md) document.
Thanks to the efforts of the amazing folks at @mercedes-benz, GARM can now be integrated into k8s via their operator. Check out the [GARM operator](https://github.com/mercedes-benz/garm-operator/) for more details.
The ```GARM``` configuration is a simple ```toml```. The sample config file in [the testdata folder](/testdata/config.toml) is fairly well commented and should be enough to get you started. The configuration file is split into several sections, each of which is documented in its own page. The sections are:
GARM is designed with simplicity in mind. At least we try to keep it as simple as possible. We're aware that adding a new tool in your workflow can be painful, especially when you already have to deal with so many. The cognitive load for OPS has reached a level where it feels overwhelming at times to even wrap your head around a new tool. As such, we believe that tools should be simple, should take no more than a few hours to understand and set up and if you absolutely need to interact with the tool, it should be as intuitive as possible.
We've written a short introduction into some of the commands that GARM has and some of the concepts involved in setting up GARM, managing runners and how GitHub does some of the things it does.
[You can find it here](/doc/using_garm.md).
Please, feel free to [open an issue](https://github.com/cloudbase/garm/issues/new) if you find the documentation lacking and would like more info. Sometimes we forget the challanges that new users face as we're so close to the code and how it works. Any feedback is welcome and we're always looking to improve the documentation.
GARM uses providers to create runners in a particular IaaS. The providers are external executables that GARM calls into to create runners. Before you can create runners, you'll need to install at least one provider.
If you would like to optimize the startup time of new instance, take a look at the [performance considerations](/doc/performance_considerations.md) page.
The providers are interfaces between ```GARM``` and a particular IaaS in which we spin up GitHub Runners. **External** providers can be written in any language, as they are in the form of an external executable that ```GARM``` calls into. Please see the [Writing an external provider](/doc/external_provider.md) document for details. Also, feel free to inspect the two available sample external providers in this repository.
