Part of the idea behind stacked PRs is to keep your commits focused and with isolated changes that are meaningful.

A stacked PR allows you to construct a sequence of PRs in a way that allows you to iterate on and merge the isolated commits, but blocks merging items higher in the stack until the foundational changes are merged.

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noident 8 hours ago | parent [-]

What can stacked PRs do that a series of well-organized commits in a single branch can't?

	▲	steveklabnik 7 hours ago \| parent [-]
		Stacked PRs tend to encourage a series of well-organized commits, because you review each commit separately, rather than together. What they do that the single branch cannot is things like "have a disjoint set of reviewers where some people only review some commits", and that property is exactly why it encourages more well-organized commits, because you are reviewing them individually, rather than as a massive whole. They also encourage amending existing commits rather than throwing fixup commits onto the end of a branch, which makes the original commit better rather than splitting it into multiple that aren't semantically useful on their own.