Taps are external sources of Homebrew formulae and/or external commands. They can be created by anyone to provide their own formulae and/or external commands to any Homebrew user.
A tap is usually a Git repository available online, but you can use anything as long as it’s a protocol that Git understands, or even just a directory with files in it. If hosted on GitHub, we recommend that the repository’s name start with homebrew- so the short brew tap command can be used. See the manpage for more information on repository naming.
Tap formulae follow the same format as the core’s ones, and can be added at the repository’s root, or under Formula or HomebrewFormula subdirectories. We recommend the latter options because it makes the repository organisation easier to grasp, and top-level files are not mixed with formulae.
See homebrew/core for an example of a tap with a Formula subdirectory.
If your formulae have the same name as Homebrew/homebrew-core formulae they cannot be installed side-by-side. If you wish to create a different version of a formula that’s in Homebrew/homebrew-core (e.g. with options) consider giving it a different name e.g. nginx-full for more fully-featured nginx formula. This will allow both nginx and nginx-full to be installed at the same time (but not linked if there are conflicts and one of them is not declared to be keg_only).
If it’s on GitHub, users can install any of your formulae with brew install user/repo/formula. Homebrew will automatically add your github.com/user/homebrew-repo tap before installing the formula. user/repo/formula points to the github.com/user/homebrew-repo/**/formula.rb file here.
If they want to get your tap without installing any formula at the same time, users can add it with the brew tap command.
If it’s on GitHub, they can use brew tap user/repo, where user is your GitHub username and homebrew-repo your repository.
If it’s hosted outside of GitHub, they have to use brew tap user/repo <URL>, where user and repo will be used to refer to your tap and <URL> is your Git clone URL.
Users can then install your formulae either with brew install foo if there’s no core formula with the same name, or with brew install user/repo/foo to avoid conflicts.
A tap is just a Git repository so you don’t have to do anything specific when making modifications, apart from committing and pushing your changes.
Once your tap is installed, Homebrew will update it each time a user runs brew update. Outdated formulae will be upgraded when a user runs brew upgrade, like core formulae.
You can provide your tap users with custom brew commands by adding them in a cmd subdirectory. Read more on external commands.
See homebrew/aliases for an example of a tap with external commands.
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Licensed under the BSD 2-Clause License.
https://docs.brew.sh/How-to-Create-and-Maintain-a-Tap