gitbutler-stacks

name	gitbutler-stacks
description	This skill should be used when creating stacks, dependent branches, or when "stack", "stacked branches", "anchor", "--anchor", "but branch new -a", "create dependent branch", or "break feature into PRs" are mentioned with GitButler. Covers anchor-based stacking for dependent features and reviewable PR breakdown.
metadata	{"version":"1.0.0","author":"outfitter","category":"version-control","related-skills":["gitbutler-virtual-branches","gitbutler-complete-branch","gitbutler-multi-agent"]}

GitButler Stacks

Dependent branches → anchor-based stacking → reviewable chunks.

<when_to_use>

• Sequential dependencies (e.g., refactor → API → frontend)
• Large features broken into reviewable chunks
• Granular code review (approve/merge early phases independently)
• Post-hoc stack organization after exploratory coding

NOT for: independent parallel features (use virtual branches), projects using Graphite stacking

</when_to_use>

Stacked vs Virtual Branches

Type	Use Case	Dependencies
Virtual	Independent, unrelated work	None — parallel
Stacked	Sequential dependencies	Each builds on parent

Stacked branches = virtual branches split into dependent sequence. Default: Virtual branches are stacks of one.

Creating Stacks

# Base branch (no anchor)
but branch new base-feature

# Stacked branch (--anchor specifies parent)
but branch new child-feature --anchor base-feature

# Third level
but branch new grandchild-feature --anchor child-feature

Result: base-feature ← child-feature ← grandchild-feature

Short form: -a instead of --anchor

but branch new child -a parent

Stack Patterns

Common patterns: feature dependency chains, refactoring sequences, deep stacks.

Example - Feature Dependency:

but branch new auth-core
but branch new auth-oauth --anchor auth-core
but branch new auth-social --anchor auth-oauth

See references/patterns.md for detailed patterns with commit examples.

Post-Hoc Stack Organization

Convert independent branches into a stack by recreating with correct anchors:

1. Create new branch with --anchor pointing to intended parent
2. Move commits with but rub <sha> <new-branch>
3. Delete original branch

See references/reorganization.md for detailed workflows.

Publishing Stacks

Using CLI (Preferred)

# Push and create PR for a branch
but push dependent-feature
but pr new dependent-feature

# Push all unpushed branches
but push

but push + but pr new handles:

• Pushing branches to remote
• Creating PRs with correct base branches
• Updating existing PRs if already created

Using GitHub CLI (Alternative)

# Push branches
git push -u origin base-feature
git push -u origin dependent-feature

# Create PRs with correct base branches
gh pr create --base main --head base-feature \
  --title "feat: base feature" \
  --body "First in stack"

gh pr create --base base-feature --head dependent-feature \
  --title "feat: dependent feature" \
  --body "Depends on base-feature PR"

GitHub Settings

• Enable automatic branch deletion after merge
• Use Merge strategy (recommended) — no force pushes needed
• Merge bottom-to-top (sequential order)

Conflict Handling in Stacks

GitButler resolves conflicts per-commit during rebase:

1. When base branch updates, dependent commits rebase automatically
2. Conflicted commits marked but don't block other commits
3. Resolve conflicts per affected commit
4. Partial resolution can be saved and continued later

# Update base (may trigger rebases in stack)
but pull

# Check which commits have conflicts
but status

# Resolve in editor, GitButler auto-detects resolution

Unlike git rebase: Remaining commits continue rebasing even if some conflict.

Stack Reorganization

Key operations for restructuring stacks:

Operation	Command
Squash commits	but squash <branch> or but rub <newer> <older>
Move commit	but rub <sha> <target-branch>
Split branch	Create anchored branch, move commits

See references/reorganization.md for detailed examples.

Stack Navigation

Note: Virtual branches don't need checkout — all branches active simultaneously.

# View full stack structure
but status

# Work on any branch directly (no checkout needed)
but commit base-feature -m "update base"
but commit dependent-feature -m "update dependent"

# Inspect a specific branch
but show dependent-feature

# JSON for programmatic analysis
but show dependent-feature --json | jq '.commits[] | .id'

ALWAYS:

• Create stacks with --anchor from the start
• Merge stacks bottom-to-top (base first, dependents after)
• Snapshot before reorganizing: but oplog snapshot --message "Before stack reorganization"
• Keep each level small (100-250 LOC) for reviewability
• Delete empty branches after reorganization

NEVER:

• Skip stack levels when merging
• Stack independent, unrelated features (use virtual branches)
• Create deep stacks (5+ levels) without good reason
• Forget anchor when creating dependent branches

Troubleshooting

Symptom	Cause	Solution
Stack not showing in but status	Missing --anchor	Recreate with correct anchor
Commits in wrong stack level	Wrong branch targeted	but rub <sha> correct-branch
Can't merge middle of stack	Wrong order	Merge bottom-to-top only

Recovery

To fix a branch with wrong/missing anchor: create new branch with correct anchor, move commits with but rub, delete original.

See references/reorganization.md for complete recovery procedures.

Best Practices

Planning

• Start simple: 2-3 levels max initially
• Single responsibility per level
• Only stack when there's a real dependency

Maintenance

• Run but status regularly to verify structure
• Commit to correct branches immediately
• Clean up empty branches

Communication

• Clear commit messages explaining why stack level exists
• Descriptive names indicating stack relationship
• Share but status when coordinating

Reference Files

• references/patterns.md — Detailed stack patterns (feature dependency, refactoring, deep stacks)
• references/reorganization.md — Post-hoc organization, squashing, moving commits, splitting

Related Skills

• gitbutler-virtual-branches — Core GitButler workflows
• gitbutler-complete-branch — Merging to main
• gitbutler-multi-agent — Multi-agent coordination

External

• GitButler Stacks Docs
• Stacked Branches Blog