Technology

Postman & Karate Testing& Development

APIs are where integration bugs live. We use Postman for exploratory and collection-based coverage and Karate for BDD-style automated API suites, validating REST, GraphQL, and SOAP services on contracts, auth, error handling, and edge cases before any frontend depends on them.

API functional, contract, and Automation tooling

Functional and negative API coverage (REST · GraphQL · SOAP)

Contract/schema validation with breaking-change gates in CI

Karate BDD suites your whole team can read

Auth, rate-limit, and failure-mode Testing

Tools
Postman and Newman, Karate, plus schema validation tooling
Protocols
REST, GraphQL and SOAP, including legacy WSDL estates
Runs in
Your CI, on every merge, not on somebody's laptop
Also covers
Consumer-driven contract Testing between services

Choosing between Postman and Karate

Both are good tools for different team shapes, and the wrong choice is usually made for the wrong reason.

Both are good tools for different team shapes, and the wrong choice is usually made for the wrong reason. Postman wins on accessibility: collections are readable by people who do not write code, mocking and documentation come for free, and Newman runs the same collections in CI. It suits teams where QA Engineers, developers and sometimes product people all need to touch the API surface.

Karate wins on expressiveness at scale. Its DSL keeps a large suite readable, native JSON and XML assertion is far less verbose than hand-rolled comparisons, and parallel execution, data-driven scenarios and built-in reporting come as standard. It suits engineering-led teams running hundreds of API scenarios who want everything in the repository under review. We recommend based on who will maintain the suite in a year, not on which tool is currently fashionable.

What the suites actually cover

Happy-path requests are the least valuable part of an API suite.

Happy-path requests are the least valuable part of an API suite. The defects live in the negative space: malformed payloads, missing or expired authentication, authorisation boundaries between roles and tenants, rate-limit and throttling behaviour, idempotency on retried requests, pagination and sorting edges, and the error contract itself, because a 200 response carrying an error body breaks every consumer that trusted the status code.

On top of that we add schema validation for every response the product depends on, and consumer-driven contract tests where services deploy independently, so an incompatible change fails the provider's build rather than a downstream team's environment two weeks later. The full discipline is on our API Testing page, and the practical write-up is Shift-Left API Contract Testing.

Mocks, environments and CI

Suites that depend on a third party's availability are not tests, they are alarms.

Suites that depend on a third party's availability are not tests, they are alarms. We build a mock layer that reproduces timeouts, rate limits, error payloads and malformed responses on demand, so failure paths are covered repeatably and the pipeline's reliability is not hostage to somebody else's uptime. Environments and secrets are parameterised, collections and feature files are version-controlled alongside the application, and reporting names the failing contract rather than dumping a diff.

Engagement path

How the engagement runs

How a Postman & Karate engagement runs from first call to handover.

01

Surface inventory

Endpoints catalogued, OpenAPI or GraphQL schema reviewed where one exists, and the gaps between documented and actual behaviour flagged.

02

Tool fit decision

Postman or Karate chosen on who maintains the suite in a year, then structured so it stays readable as scenario count grows.

03

Negative and contract coverage

Auth boundaries, rate limits, error contracts and schema validation, plus consumer-driven contracts in the right pipelines.

04

Mocking and CI wiring

Third-party failure simulated on demand, environments parameterised, and the suite running on every merge with actionable reporting.

Deliverables

What you get

Artefacts you keep and can run without us. Everything lives in your repositories and your pipelines.

Handover pack

6 artefacts · yours to keep

01

Postman collections or Karate feature files version-controlled in your repository

02

Schema validation for every response your product depends on

03

Negative, auth-boundary and rate-limit coverage beyond the happy path

04

Consumer-driven contract tests running in provider pipelines

05

A mock layer reproducing third-party failure modes on demand

06

CI execution via Newman or the Karate runner with actionable reports

Self-check

Signs your team needs this

If more than one of these is true, it is usually cheaper to fix now than after the next release.

API tests exist in someone's Postman workspace and nowhere else

The frontend team finds integration bugs before any pipeline does

There is no schema of record, or schema and reality have drifted

Error responses are inconsistent and consumers each handle them differently

A third party's downtime turns your test suite red

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Questions

Frequently Asked Questions

Straight answers, written the way we'd say them on a call.

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16+

Years QA leadership

16

Testing disciplines

6

Markets served

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