wtf is gha-self-hosted?

GitHub Actions lets projects automate tasks like running tests and building releases, but doing that on GitHub's own shared computers can be slow or limiting. This repository gives the Rust programming language project its own private computers, called "self-hosted runners," to handle that automated work instead. At a high level, the production servers automatically check this repository every 15 minutes. If anything changed in the images folder, they rebuild the machine images, which are essentially blueprints for what software and settings the runners need to operate. This setup keeps the runners consistently configured without someone having to manually update each one. The audience here is narrow by design. The tools are built specifically for the Rust Infrastructure Team to manage the project's own testing and automation environment. The documentation explicitly notes that they do not intend to support anyone else using these tools and warns that breaking changes might happen at any time. For anyone curious about how a large open-source project manages its own automation infrastructure behind the scenes, this offers a straightforward example. The README is sparse on operational details, pointing instead to a separate internal documentation site for instructions on how the deployment actually works.