Acceptable-Formulae.md

Acceptable Formulae

Some formulae should not go in homebrew/core. But there are additional Interesting Taps & Forks and anyone can start their own!

We try hard to avoid dupes in Homebrew/homebrew

Stuff that comes with macOS or libraries that are provided by RubyGems, CPAN or PyPi should not be duplicated. There are good reasons for this:

• Duplicate libraries regularly break builds
• Subtle bugs emerge with duplicate libraries, and to a lesser extent, duplicate tools
• We want our formulae to work with what comes with macOS

There are exceptions:

• OpenSSL - Apple has formally deprecated OpenSSL on macOS in favour of their own Security Framework & consequently the macOS OpenSSL is rarely updated and frequently falls behind important security updates. Homebrew endeavours to use our shipped OpenSSL as much as possible.
• Programs that a user will regularly interact with directly, like editors and language runtimes
• Libraries that provide functionality or contain security updates not found in the system version
• Things that are designed to be installed in parallel to earlier versions of themselves

Examples

Formula	Reason
ruby, python, perl	People want newer versions
bash	macOS's bash is stuck at 3.2 because newer versions are licensed under GPLv3
zsh	This was a mistake, but it’s too late to remove it
emacs, vim	Too popular to move to dupes
subversion	Originally added for 10.5, but people want the latest version
libcurl	Some formulae require a newer version than macOS provides
openssl	macOS's openssl is deprecated & outdated.
libxml2	Historically, macOS's libxml2 has been buggy

We also maintain a tap that contains many duplicates not otherwise found in Homebrew.

We don’t like tools that upgrade themselves

Software that can upgrade itself does not integrate well with Homebrew's own upgrade functionality.

We don’t like install-scripts that download things

Because that circumvents our hash-checks, makes finding/fixing bugs harder, often breaks patches and disables the caching. Almost always you can add a resource to the formula file to handle the separate download and then the installer script will not attempt to load that stuff on demand. Or there is a command line switch where you can point it to the downloaded archive in order to avoid loading.

We don’t like binary formulae

Our policy is that formulae in the core repository (homebrew/core) must be open-source and either built from source or produce cross-platform binaries like e.g. Java). Binary-only formulae should go to Homebrew Cask.

Stable versions

Formulae in the core repository must have a stable version tagged by the upstream project. Tarballs are preferred to git checkouts, and tarballs should include the version in the filename whenever possible.

Software that only provides a development/beta, tagged version should be put in homebrew/devel-only. We don’t accept software without a tagged version because they regularly break due to upstream changes; we can’t provide bottles for them; and we don’t have an automatic update mechanism for head-only formulae which makes them very quickly outdated.

Bindings

First check that there is not already a binding available via gem or pip etc..

If not, then put bindings in the formula they bind to. This is more useful to people. Just install the stuff! Having to faff around with foo-ruby foo-perl etc. sucks.

Niche (or self-submitted) Stuff

The software in question must be

• maintained (e.g. upstream is still making new releases)
• known
• stable (e.g. not declared "unstable" or "beta" by upstream)
• used
• have a homepage

We will reject formulae that seem too obscure, partly because they won’t get maintained and partly because we have to draw the line somewhere.

We frown on authors submitting their own work unless it is very popular.

Don’t forget Homebrew is all git underneath! Maintain your tap if you have to!

There may be exceptions to these rules in the main repository, we may include things that don't meet these criteria or reject things that do. Please trust that we need to use our discretion based on our experience running a package manager.

Stuff that builds an .app

Don’t make your formula build an .app (native macOS Application); we don’t want those things in Homebrew (but Homebrew Cask does). Make it build a command-line tool or a library.

Sometimes there are exceptions

Even if all criteria are met we may not accept the formula. Documentation tends to lag behind current decision-making. Although some rejections may seem arbitrary or strange they are based from years of experience making Homebrew work acceptably for our users.