Restrict GitHub branches to specific prefixes

Many people follow some kind of naming format for their branches. Be it because they’re using GitHub Flow or Git Flow or because they’ve created their own meaningful naming patterns.

With the new Rulesets you can enforce branches with specific patterns. It was a bit confusing to me at first, because I had to think in inverse to make this rule work.

If you are on GitHub Enterprise you can use the metadata restrictions feature of the new Repository Rulesets feature:

But if you are on a different plan (free, team), here’s a trick that will also do the job.

Create a rule that restricts the creation of any branch **, then selectively excludes prefixes from this restriction:

Include pattern:

• **

Exclude pattern:

• fix/*<em>/</em>
• release/*<em>/</em>
• main

Then turn on ✅ Restrict creations.

In case you need specific GitHub apps (such as Dependabot and Renovate or Azure Pipelines) to create arbitrary branch names, you can exclude them from the policy:

Title photo by Marco Verch: Train Light Signal, used under Creative Commons