Verification

• This issue's title and/or description do not reference a single formula e.g. brew install wget. If they do, open an issue at https://github.com/Homebrew/homebrew-core/issues/new/choose instead.

Provide a detailed description of the proposed feature

Add Flatpak package and remote support to brew bundle, similar to the existing support for formulae, casks, Mac App Store apps, VSCode extensions, and Go packages.

This would allow users to:

• Declare Flatpak remotes in their Brewfile using a flatpak_remote DSL method
• Declare Flatpak applications in their Brewfile using a flatpak DSL method
• Dump installed Flatpak remotes and applications to a Brewfile with brew bundle dump --flatpak --flatpak-remotes
• Install Flatpak remotes and applications from a Brewfile with brew bundle install
• Check if Flatpak remotes and applications are installed with brew bundle check
• List Flatpak entries with brew bundle list --flatpak --flatpak-remotes
• Clean up unused Flatpak remotes and applications with brew bundle cleanup

What is the motivation for the feature?

Flatpak is increasingly popular on Linux systems as a universal packaging format, and many Linux users who use Homebrew also use Flatpak for GUI applications. Currently, users need to manage their Flatpak installations separately from their Brewfile, which breaks the unified dependency management that brew bundle provides.

With Flatpak support in brew bundle, users could:

1. Maintain a single source of truth for all their system packages (Homebrew formulae/casks + Flatpak apps/repos)
2. Easily replicate their setup across multiple Linux machines using one Brewfile
3. Version control their complete system configuration including GUI applications that are often only available via Flatpak
4. Automate system setup more completely for Linux development environments

This is particularly useful for:

• Linux users who use both Homebrew (for CLI tools) and Flatpak (for GUI apps)
• Teams standardizing development environments across Linux workstations
• System administrators managing multiple Linux machines
• Users who want reproducible Linux desktop setups

How will the feature be relevant to at least 90% of Homebrew users?

All Linux homebrew users can benefit from being able to administer their Flatpak installations and repos via a Brewfile.

What alternatives to the feature have been considered?

We briefly explored plugins but as we'd want this to be opaque to the user we thought moving this upstream this would be beneficial.