Journey Lanes, Playwright and Postman: which one when?

When Playwright is the better choice

Playwright is a test framework for browsers and APIs that you program in code, kept in your repository and run in your pipeline. Choose hand-written Playwright tests when:

• you need to test what people see and do in the browser: layout, forms, client-side logic, accessibility;
• your team prefers tests as code, reviewed in pull requests next to the feature;
• the test needs logic that’s easier to write than to describe: loops, branching on data, custom assertions.

When Postman is the better choice

Postman is an API client with collections you can share and run. Choose it when:

• developers explore and debug an API by hand, request by request;
• you want to document an API with example requests your team can send;
• a collection of checks per endpoint is enough, and the team already knows the tool.

When Journey Lanes fits

Journey Lanes is built for API journeys per role, from your own code, kept running over time. It fits when:

• you want flows from a catalog of your real endpoints, records and roles, read from your code or API descriptions, rather than from an empty file (sources);
• people outside engineering should read and change the journeys: a flow is drawn from a plain-language sentence with a lane per role (flows);
• roles and tenants matter: each role signs in its own way, and an access audit probes every endpoint with every role and tenant (checks and audits);
• you need a backend before yours is ready: a mock built from your entities, scoped per role (mock backend);
• monitoring, alerts and deploy checks should come with it, not be built around it (monitoring).

It doesn’t test screens in a browser: its sign-in browser is only used for login pages that need JavaScript. For UI behaviour, use a browser test.

Using them together

Any Journey Lanes flow exports as a Playwright test (using the @playwright/test request fixture) or as a Postman collection (v2.1), and as a flow file that imports again (CI and exports). A common split: Journey Lanes for the journeys per role, access audits and monitoring; Playwright for the browser; Postman for exploring an API by hand.

Questions to ask when choosing

1. Who writes and maintains the tests? If only developers, tests as code fit well. If testers and product owners should change them too, a tool they can read without code helps.

2. What do the tests need to see? Screens and client-side behaviour need a browser test. Rules about who may do what, and the data that comes back, are tested most reliably through the API.

3. How many roles and tenants does your product have? With one kind of user, a single happy-path test may do. With several roles and customers that must not see each other’s data, every journey needs a version per role, and an audit across them.

4. Is there a backend to test against yet? If the API is still being built, a mock that follows its code lets the frontend and the tests start now.

5. What happens after the release? Tests that run only in CI tell you about the build. Journeys that keep running against production tell you about the product.

Most teams end up with more than one tool. The point is to know which questions each one answers, so nothing important is left to a test nobody runs.

In short