# Homebrew downloads

Avrea caches [bottles (binary packages)](https://docs.brew.sh/Bottles) for
`homebrew/core` formulae, Homebrew API metadata, and public GitHub source
archives on Linux and macOS runners.
Use `brew install` as usual; installation still happens on each runner.

## Enable

Enable **Package Manager Cache** and **Homebrew Download Cache** in organization
or repository settings. Homebrew caching is off by default and applies to new
jobs and refreshed hosted environments.

## Coverage

Bottles, including those for versioned formulae, are shared across runners.
Metadata refreshes after five minutes. Homebrew's checksum and signed metadata
verification remain enabled.

Public GitHub source archives using full commit SHAs or explicit tag URLs
are also cached.

Other source archives, cask downloads, and bottles from other taps are not covered.
Leave `HOMEBREW_ARTIFACT_DOMAIN_NO_FALLBACK` unset so Homebrew can download
unsupported files directly. Some GitHub-hosted downloads may use the separate
[GitHub Release Asset Cache](/cache/packages/github-release-assets/).

## Custom mirrors

Enabling the cache sets these environment variables:

```bash
HOMEBREW_ARTIFACT_DOMAIN="https://cache.avrea.com:8443/homebrew"
HOMEBREW_API_DOMAIN="https://cache.avrea.com:8443/homebrew/api"
```

In GitHub Actions, override these values with step-level `env` entries;
workflow- and job-level entries can be superseded by Avrea's `GITHUB_ENV` values.

View activity under **Homebrew · Downloads**. Turn off **Homebrew Download Cache**
to stop configuring the mirrors. Cache URLs are accessible only inside Avrea runners.