AI writes 2,000 lines in one shot.
Stack them.
Stacks turns every commit on your branch into its own pull request. One local branch with standard Git, each commit its own focused PR. Reviewers see small diffs. Your merge queue handles the rest.
Code review, unblocked.
PR #421 ← refactor: extract auth middleware ✓ created PR #422 ← feat: add OAuth2 provider support ✓ created PR #423 ← feat: add token refresh logic ✓ created PR #424 ← test: add auth integration tests ✓ created
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Clément Danjou, VP Blockchain
The 2,000-line PR that nobody actually reviews
An AI agent refactors your authentication layer in 40 minutes. It touches 47 files and produces a single pull request with 2,100 lines changed. Two reviewers approve it within an hour. Neither read past the first 300 lines.
This is the new normal. AI coding tools generate complete, working changesets at a pace that makes large PRs inevitable. The code is often correct. The reviews are almost never thorough. When something breaks in production, nobody can point to which change caused it because the diff was a wall of text that got a rubber-stamp approval.
The problem is structural. You can't review what you can't hold in your head.
Problems that multiply with every AI-generated changeset
The bigger your PRs get, the worse each of these becomes.
Reviews become theater
Review quality drops sharply after 400 lines. A 2,000-line PR gets surface-level skimming and a polite "LGTM." Bugs hide in the parts nobody read.
Rollbacks take the whole feature
When one change in a monolithic PR causes a production issue, you revert everything. The 90% of changes that were fine get rolled back too.
Review bottlenecks multiply
Large PRs sit in review queues for days because nobody has 2 hours to read them. Smaller PRs get reviewed in minutes. The throughput difference compounds across a team.
Context is impossible to transfer
When an AI agent writes code across 47 files, the reviewer reconstructs the agent's reasoning from the diff alone. Stacking gives each PR a clear, single purpose.
We went from PRs sitting in review for days to getting them merged the same afternoon. Stacking forced us to write smaller, clearer commits. Reviewers stopped procrastinating because each PR was a 10-minute read, not a 2-hour slog.
Marie Laurent
Senior Software Engineer at SG
Same code, same branch, four reviewable PRs
Stacks maps each commit on your branch to its own pull request. You keep working in a single local branch with standard Git. Mergify handles the PR chain and keeps everything in sync. Reviewers see 200-line diffs, not 2,000-line walls.
One branch, many PRs
Each commit becomes a separate PR with its own reviewers, CI run, and approval status. Your local workflow stays a single branch with standard Git commands.
Automatic dependency chain
Stacks sets the base branch of each PR to the previous PR in the chain. GitHub shows only that PR's diff, not the cumulative change. Reviewers see exactly what changed in that commit.
Five commands. That's the whole workflow.
No GUI, no new branching model. Stacks works inside your terminal with the Git commands you already know.
PR #421 ← refactor: extract auth middleware ✓ PR #422 ← feat: add OAuth2 provider support ✓ PR #423 ← feat: add token refresh logic ✓
Smart updates
Amend a commit and push again. Only the PR for that commit gets updated. The others keep their reviews and CI status intact.
Merge queue integration
When the first PR in the chain is approved, it enters the merge queue. After it merges, the next PR automatically becomes merge-ready.
Review in GitHub directly
No external app, no extra dashboard. Stacked PRs are regular GitHub pull requests. Your reviewers use the tools they already know.
Already drowning in AI-generated PRs?
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Built for the age of AI-generated code
AI coding agents don't think in small PRs. They think in complete features. Stacks is the missing layer between AI output and human review.
Change-Id persistence
Every commit gets a unique Change-Id that survives rebases and amends. When you push again, Stacks matches commits to their existing PRs. No duplicate PRs. No lost review context.
Skip what didn't change
When you amend commit #2 in a 5-commit stack and push, only PR #2 gets updated. PRs #1, #3, #4, and #5 keep their approvals and CI status. Reviewers re-review only what actually changed.
Our AI coding agent kept producing 1,500-line PRs. Nobody wanted to review them, so they sat open for a week. Stacks turned those into four or five focused PRs that went through review in a day. It changed how our whole team works with AI-generated code.
Erik Johansson
Platform Engineer at Wavefront
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Real teams, real results
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Stop shipping 2,000-line PRs
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