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‎src/content/docs/merge-queue.mdx‎

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@@ -110,14 +110,18 @@ quickly consume significant compute resources and budget.
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**The Solution:** A merge queue enables several cost-saving strategies:
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- **[Batch merging](/merge-queue/batches)**: Combine multiple PRs into a single
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batch and test them together. Instead of running CI separately for 5 PRs, run
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it once for all 5 together, drastically reducing CI usage.
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batch and test them together. Instead of running CI separately for 5 PRs, run
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it once for all 5 together, drastically reducing CI usage.
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- **[Scope-aware batching](/merge-queue/scopes)**: Attach scopes to pull
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requests so Mergify groups related changes together. Shared test runs can be
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reused, making batching safer and more efficient—especially in monorepos.
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- **[Two-step CI](/merge-queue/two-step)**: Move expensive tests (like E2E
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tests) to run only in the merge queue instead of on every PR update. Since
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PRs often get updated multiple times before merging—or may never merge at
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all—this can dramatically reduce CI costs while actually improving reliability
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by ensuring those critical tests run against the real merge state.
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tests) to run only in the merge queue instead of on every PR update. Since
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PRs often get updated multiple times before merging—or may never merge at
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all—this can dramatically reduce CI costs while actually improving reliability
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by ensuring those critical tests run against the real merge state.
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With these strategies, you can significantly reduce CI costs compared to running
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all tests on every PR update, while simultaneously gaining better reliability

‎src/content/docs/merge-queue/monorepo.mdx‎

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@@ -8,6 +8,8 @@ every change wastes time and CI resources. Mergify's **scopes** feature allows y
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batch pull requests based on which parts of your codebase they modify, dramatically improving merge
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queue efficiency.
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For a deep dive into how scopes influence batching, see [Merge Queue Scopes](/merge-queue/scopes).
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## Understanding Scopes
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Scopes define discrete areas of your monorepo (like packages, services, or components). When a pull

‎src/content/docs/merge-queue/scopes.mdx‎

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---
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title: Merge Queue Scopes
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description: Understand how Mergify groups pull requests by scope to build the most effective batches.
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---
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Mergify scopes describe the areas of your codebase that a pull request touches. By attaching scopes
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to pull requests, the merge queue can build smarter batches, reuse the same CI work, and avoid
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mixing unrelated changes.
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## Scope-aware batching at a glance
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When several pull requests are eligible for the next batch, Mergify compares their scopes and
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prioritizes the combination that shares the most scopes in common. Pull requests that overlap in
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scope are tested together first, while unrelated changes stay in the queue until a compatible batch
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is available or Mergify needs them to fill the requested batch size.
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```dot class="graph"
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strict digraph {
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fontname="sans-serif";
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rankdir="LR";
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label="Scope-aware Batch Selection";
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nodesep=0.9;
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ranksep=1.2;
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splines=polyline;
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edge [fontname="sans-serif", color="#374151", arrowhead=none, penwidth=1.2];
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subgraph cluster_preferred {
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style="rounded";
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color="#1CB893";
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label="Preferred batch";
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PR1 [shape=box, style="rounded,filled", fillcolor="#347D39", fontcolor="white", color="#165B33", margin="0.35,0.22", fontname="sans-serif", label="PR #101\nScopes: frontend, api"];
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PR2 [shape=box, style="rounded,filled", fillcolor="#347D39", fontcolor="white", color="#165B33", margin="0.35,0.22", fontname="sans-serif", label="PR #214\nScopes: frontend"];
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PR3 [shape=box, style="rounded,filled", fillcolor="#347D39", fontcolor="white", color="#165B33", margin="0.35,0.22", fontname="sans-serif", label="PR #305\nScopes: api, docs"];
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}
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PR4 [shape=box, style="rounded,filled", fillcolor="#6B7280", fontcolor="white", color="#4B5563", margin="0.35,0.22", fontname="sans-serif", label="PR #412\nScope: tooling"];
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frontend [shape=oval, style="filled", fillcolor="#1CB893", fontcolor="#063C2C", color="#0B7A5C", margin="0.3,0.18", fontname="sans-serif", label="frontend"];
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api [shape=oval, style="filled", fillcolor="#1CB893", fontcolor="#063C2C", color="#0B7A5C", margin="0.3,0.18", fontname="sans-serif", label="api"];
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docs [shape=oval, style="filled", fillcolor="#1CB893", fontcolor="#063C2C", color="#0B7A5C", margin="0.3,0.18", fontname="sans-serif", label="docs"];
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tooling [shape=oval, style="filled", fillcolor="#1CB893", fontcolor="#063C2C", color="#0B7A5C", margin="0.3,0.18", fontname="sans-serif", label="tooling"];
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PR1 -> frontend;
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PR1 -> api;
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PR2 -> frontend;
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PR3 -> api;
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PR3 -> docs;
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PR4 -> tooling;
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}
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```
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In the example above, the queue selects the three pull requests that share the `frontend` and `api`
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scopes first. The change that only touches the `tooling` scope is kept aside unless Mergify needs it
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later to complete the batch.
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## How Mergify builds scope-aware batches
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Scope-aware batching follows these steps:
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1. **Collect candidates:** Mergify looks at the next pull requests in queue order that pass the
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queue rules and are ready to batch.
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2. **Score overlap:** It evaluates how many scopes each candidate shares with the already selected
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pull requests and prefers combinations with the highest overlap.
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3. **Fill the batch:** If the required `batch_size` is not reached with strongly overlapping scopes,
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Mergify expands the selection to the best remaining options so the batch can
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still start.
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4. **Fallback safely:** When no scope overlap exists, the queue still batches the oldest pull
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requests together to honor throughput, but these situations are the exception rather than the
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rule.
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This strategy maximizes CI reuse: tests that run for one pull request are likely valid for the other
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changes in the batch because they touch the same areas of the codebase.
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## Scope assignment lifecycle
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Scopes can be attached to pull requests automatically or manually:
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- **File pattern detection:** Define scopes directly in your configuration so Mergify infers them
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from changed paths once your CI uploads the results via
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[`gha-mergify-ci`](https://github.com/Mergifyio/gha-mergify-ci) or an equivalent integration.
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See [file-pattern scopes](/merge-queue/monorepo/file-patterns) for a
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step-by-step setup.
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- **Manual upload:** Use the [`gha-mergify-ci`](https://github.com/Mergifyio/gha-mergify-ci)
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GitHub Action, the REST API, or the `mergify scopes-send` CLI to push scopes computed by your own
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tooling (Nx, Bazel, Turborepo, etc.). Examples are available in the build tool guides under
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[Monorepo integrations](/merge-queue/monorepo).
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## Configuration schema
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Declare scopes at the top level of your `.mergify.yml` file:
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```yaml
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scopes:
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source:
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files:
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frontend:
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includes:
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- apps/web/**/*
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api:
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includes:
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- services/api/**/*.py
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docs:
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includes:
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- docs/**/*
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merge_queue_scope: merge-queue
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queue_rules:
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- name: default
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batch_size: 3
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```
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### Top-level keys
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- `scopes.source`: selects how scopes are provided.
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- `files`: map scope names to the file patterns that define them. Each entry accepts `includes`
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and optional `excludes` lists.
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- `manual`: instructs Mergify to expect scopes from external systems via the API or GitHub
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Action.
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- `null`: disables scopes entirely.
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- `scopes.merge_queue_scope`: optional name automatically applied to temporary merge queue pull
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requests (defaults to `merge-queue`). Set it to `null` to disable.
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### Manual source example
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```yaml
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scopes:
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source:
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manual:
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queue_rules:
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- name: default
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batch_size: 5
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```
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With the configuration above you must push scopes yourself—typically from a CI job that analyses the
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pull request and calls `gha-mergify-ci` with the `scopes-upload` action. This is the recommended
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approach when build systems such as Bazel, Nx, or Turborepo already know which projects are affected.
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## Best practices
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- Keep scope names stable and small in number so batches stay meaningful.
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- Prefer scopes that align with your CI topology—if a test suite covers a specific service or
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package, create a scope with the same boundary.
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- Still configure sane `batch_max_wait_time` values: scopes help Mergify pick the right pull
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requests, but you control how long it waits for an ideal batch.
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- Monitor merge queue analytics to verify that scope-aware batching increases success rate and
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reduces redundant CI runs; adjust scope definitions when you see batches mixing unrelated changes.

‎src/content/navItems.tsx‎

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FaBug,
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FaCircleXmark,
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FaGear,
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FaLayerGroup,
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FaMoneyBill1,
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FaRegCircleCheck,
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FaRegCirclePause,
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{ title: 'Performance', path: '/merge-queue/performance', icon: SlSpeedometer },
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{ title: 'Parallel Checks', path: '/merge-queue/parallel-checks', icon: TiFlowParallel },
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{ title: 'Batches', path: '/merge-queue/batches', icon: TbPackages },
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{ title: 'Scopes', path: '/merge-queue/scopes', icon: FaLayerGroup },
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{ title: 'Two-Step CI', path: '/merge-queue/two-step', icon: FaStairs },
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{
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title: 'Monorepo',

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