Merge Checks

Use WorkerRun as a final merge gate that runs after your CI passes.

A common pattern is to run your full CI pipeline (lint, test, build) on standard runners, then use WorkerRun for a lightweight final check before merging. Because the merge gate only needs to call the GitHub API, it completes in milliseconds on a V8 isolate — no VM spin-up required.

Note: This example uses actions/github-script@v8 for inline JavaScript. WorkerRun also supports run: steps with 80+ built-in shell commands (echo, curl, jq, grep, sed, etc.) in V8 mode, and full bash in container mode. See Supported Actions for details.

Full Workflow

.github/workflows/merge-check.yml

name: Merge Check
on:
  pull_request:
    types: [opened, synchronize, labeled, unlabeled]

jobs:
  lint:
    runs-on: ubuntu-latest
    steps:
      - uses: actions/checkout@v4
      - run: bun run lint

  test:
    runs-on: ubuntu-latest
    steps:
      - uses: actions/checkout@v4
      - run: bun test

  merge-gate:
    runs-on: worker-run
    needs: [lint, test]
    steps:
      - name: Check merge readiness
        uses: actions/github-script@v8
        with:
          script: |
            const { data: pr } = await github.rest.pulls.get({
              ...context.repo,
              pull_number: context.issue.number,
            });

            const labels = pr.labels.map((l) => l.name);
            if (!labels.includes("ready to merge")) {
              core.setFailed('Missing "ready to merge" label');
              return;
            }

            if (pr.mergeable_state === "dirty") {
              core.setFailed("PR has merge conflicts");
            }

How It Works

1.The lint and test jobs run on ubuntu-latest as normal CI.
2.needs: [lint, test] ensures the merge gate only runs after both CI jobs succeed.
3.The script checks that the PR has the ready to merge label and has no merge conflicts.
4.If either check fails, the job fails and the PR cannot be merged (when configured as a required status check).