How a new branch gets its config, migrations, and functions

Supabase branches are their own projects, so three things have to land on one before you can use it: settings, schema, and edge functions. We run all three mostly in parallel when you create the branch. You create a preview branch to test a schema change. About 20 seconds later (the median), the branch is ready, with your tables, settings, and Edge Functions in place. When a branch takes longer than expected, or a step fails, you need to know what ran in between. This post walks through how a branching workflow runs in Supabase, what gets copied from your main project, where your migrations and functions come from, what order the steps run in, and what you see when something fails. Every branch belongs to a main project. How the branch gets its inputs depends on one primary question: is the branch tied to a git branch? GitHub-connected branches are tied to a git branch,…