Handling PR Merges in Stacks

When a PR in your stack is merged, you need to update dependent branches.

Bottom-Up Merging (Recommended)

Merge PRs from bottom to top of your stack:

feature-c → feature-b → feature-a → main

Merge feature-a → main
Rebase feature-b onto main
Merge feature-b → main
Rebase feature-c onto main
Merge feature-c → main

Workflow:

# After feature-a is merged into main
git checkout main
git pull

# Update feature-b to target main instead
git checkout feature-b
git rebase main

# Update the PR base on GitHub (manual or via gh CLI)
gh pr edit <pr-number> --base main

# Continue with feature-c
git checkout feature-c
git rebase main
gh pr edit <pr-number> --base main

Keeping Stack Structure (Alternative)

If you want to keep the stack structure for review purposes:

# After feature-a is merged
git checkout feature-b
git rebase main  # Rebase onto main, skipping feature-a commits

# feature-a commits are now in main, so feature-b PR shows only B changes
# PR base stays as feature-a (which now == main + A changes)

Best Practices

Merge Order

Start from the bottom: Always merge the bottom-most PR first
Sequential merging: Merge one PR at a time
Update dependencies: Rebase dependent branches after each merge

Communication

Update PR descriptions: Note which PRs have been merged
Use labels: Tag PRs with their position in the stack
Comment on status: Keep reviewers informed of stack progress

Automation

You can automate stack updates with GitHub Actions when PRs are merged. See the CI/CD Integration page for examples.

Common Scenarios

Merged Bottom PR

# feature-a has been merged to main
git checkout main
git pull

# Update feature-b
git checkout feature-b
git rebase main
git push --force-with-lease

# Update PR target
gh pr edit <pr-number> --base main

Merged Middle PR

If a middle PR gets merged before the bottom:

# feature-b was merged, but feature-a wasn't
# Now feature-c depends on feature-a

# Option 1: Merge feature-a next
# Option 2: Rebase feature-c onto feature-b (if feature-a is no longer needed)

git checkout feature-c
git rebase feature-b  # Skip feature-a entirely

Multiple PRs Ready

# If multiple PRs in your stack are approved:
# Merge them in order from bottom to top

# 1. Merge feature-a
gh pr merge <pr-a> --squash

# 2. Wait for CI, then update and merge feature-b
git checkout main && git pull
git checkout feature-b && git rebase main
git push --force-with-lease
gh pr merge <pr-b> --squash

# 3. Repeat for feature-c
git checkout main && git pull
git checkout feature-c && git rebase main
git push --force-with-lease
gh pr merge <pr-c> --squash

Handling Merges