How to Configure IIS and Playwright for Secure, Repeatable Web Testing

You push a new build to staging, hit refresh, and watch it render perfectly on localhost. Then QA opens it in Internet Explorer mode under IIS and everything breaks. That’s when the idea hits: automate this madness. That’s where IIS and Playwright finally meet.

IIS, Microsoft’s long-lived web server, still powers plenty of production workloads and intranet apps. Playwright, Microsoft’s own browser automation framework, handles end-to-end testing with surgical precision. When you join them, you get a reliable test surface that behaves exactly like your real deployment. It’s not glamorous, but it’s real-world useful.

How IIS and Playwright fit together

Playwright runs tests against web endpoints. IIS hosts those endpoints under realistic network and authentication conditions. Integrating the two bridges the gap between local mocks and production environments. Instead of hitting a lightweight Node server, Playwright drives actual IIS responses, complete with NTLM or Kerberos workflows and proper TLS termination.

Think of it as testing in your own backyard instead of a sandbox. Requests go through the same handlers, the same logging modules, and the same Windows authentication stack you’ll see in production. When the test fails, it’s not because of a missing npm dependency. It’s because your app actually broke.

Best practices for IIS and Playwright integration

Configuring properly means controlling identity flow and timeouts. Tie your service principal or test user to a minimal RBAC role. Use environment variables for credentials rather than web.config secrets. Finally, keep your site bindings predictable, ideally localhost with distinct ports per test run to avoid race conditions.

When connection errors occur, check the worker process identity first. IIS loves to impersonate users at the wrong time, and Playwright doesn’t tolerate guessing games.

Benefits of this setup

• Consistent testing under the same auth and TLS model used in production
• Early detection of permission regressions
• Realistic browser automation without cloud dependencies
• Lower flakiness than simulated mocks
• Audit-friendly logs and request traces in Windows Event Viewer

Developer experience and speed

Local developers move faster when their automation trusts the same policies ops enforces in production. Once Playwright scripts target IIS directly, you can cut flakey test retries and spend less time reproducing staging bugs. That kind of velocity boost keeps CI pipelines cleaner and deployments calmer.

Platforms like hoop.dev turn those access rules into guardrails that enforce policy automatically. With it, developers get identity-aware access to real environments without storing credentials, while audits see a consistent access trail across every test run.

Quick answer: How do I run Playwright tests against IIS?

Deploy your app to an IIS site on a known port, verify it’s reachable on localhost, and point Playwright’s browser context to that URL. Let IIS handle authentication and HTTPS. Playwright doesn’t need to know it’s testing a production-grade server; it just needs a stable endpoint.

AI copilots can now orchestrate these tests intelligently, queuing test runs against live IIS instances and validating accessibility or performance baselines automatically. Just keep secrets out of prompt contexts and treat test environments as production-grade surfaces.

In a world full of fragile automation, IIS and Playwright give you steady ground to stand on. Run what you ship, test where you host, and trust what you see.

See an Environment Agnostic Identity-Aware Proxy in action with hoop.dev. Deploy it, connect your identity provider, and watch it protect your endpoints everywhere—live in minutes.