Postman
Postman is a widely used API development and testing platform for building, sending, and automating HTTP requests against REST, GraphQL, and SOAP APIs. Beyond manual request testing, it supports scripted assertions, environment variables, request chaining, and Newman (its CLI runner) for running collections inside a CI/CD pipeline.
For manual and early-stage API testing, Postman's core loop is simple: build a request, send it, inspect the response, and save it to a collection for reuse. Where it becomes a real testing tool is in its scripting layer — pre-request scripts that set up state (like fetching an auth token) and test scripts (JavaScript assertions run against the response) that turn a manual click into a repeatable, automated check.
Collections can chain requests together, passing data from one response into the next request's variables — useful for testing multi-step flows like "create a user, then log in as that user, then fetch their profile." Environments let the same collection run against local, staging, and production configurations by swapping variable values, not editing requests.
Newman, Postman's command-line collection runner, is what makes it CI-friendly: a collection built and debugged interactively in the desktop app can run headlessly in a pipeline on every pull request, with results exported in formats CI dashboards can parse.
