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.
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
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
A Senior Engineer replies within one business day. NDA first.
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.
Coverage by protocol
One baseline, then what each protocol adds
Functional correctness is the starting point, not the finish. What changes between protocols is everything after it.
Every API, whatever it speaks
07 checksStatus codes and payloads against schema
Auth and authz boundaries, including cross-tenant access
Error handling and the shape of failure responses
Rate limits and throttling behaviour
Idempotency on retries
Pagination and sorting edge cases
Backward compatibility when a version is bumped
GraphQL
+ addsOne endpoint, so the failure modes move from the route to the query.
Query-depth and complexity limits
Field-level authorisation
N+1 behaviour under realistic queries
SOAP
+ addsLegacy estates, tested properly rather than wrapped and ignored.
Validation against WSDL
Fault contracts handled as contracts
Postman · Karate — functional and contract · JMeter or k6 when API performance is in scope
Engagement path
How the engagement runs
How a Postman & Karate engagement runs from first call to handover.
Surface inventory
Endpoints catalogued, OpenAPI or GraphQL schema reviewed where one exists, and the gaps between documented and actual behaviour flagged.
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.
Negative and contract coverage
Auth boundaries, rate limits, error contracts and schema validation, plus consumer-driven contracts in the right pipelines.
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
Postman collections or Karate feature files version-controlled in your repository
Schema validation for every response your product depends on
Negative, auth-boundary and rate-limit coverage beyond the happy path
Consumer-driven contract tests running in provider pipelines
A mock layer reproducing third-party failure modes on demand
CI execution via Newman or the Karate runner with actionable reports
Questions
Frequently Asked Questions
Straight answers, written the way we'd say them on a call.
Still curious? Talk to usKeep reading
Where to go next
Teams evaluating Postman & Karate usually read these next.
Need Postman & Karate Expertise?
Start with a scoping call or a free assessment, Engineers available within days.
- A Senior Engineer replies, not a sales layer
- Within one business day, every time
- NDA available before you share any details
16+
Years QA leadership
The founder's enterprise QA career across OTT, SaaS, e-commerce and regulated utilities. Not a team total.
17
Testing disciplines
Each one has its own page, scope and deliverables. Counted from that list, never typed by hand.
6
Markets served
Availability, not delivery history. Each market's page says plainly where we have clients and where we do not.
1
Business day to reply
A Senior Engineer answers, not an autoresponder or a scheduler.
Tell us where quality hurts
Prefer to talk? Book a 30-minute call