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Service 02 API Testing

Your integrations hold up
when it matters

We verify contracts between services, third-party integrations, and graceful error handling when dependencies fail, so the systems behind your product stay in sync.

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Signs you need this

Does this sound like your team?

If any of these are familiar, api testing is the fastest way to get ahead of it.

Integrations break silently

A partner changes something and you find out from a customer.

Errors surface as blank screens

When a dependency fails, your users see nothing useful.

No one tests the contract

Endpoints are checked manually, once, then trusted forever.

What we cover

What a typical API engagement includes

Scope is always shaped around your product and stage, but this is the ground we usually cover.

  • Contract validation between every service
  • Third-party and payment integrations under real conditions
  • Authentication, authorisation and token handling
  • Graceful error handling when dependencies fail
  • Data integrity across request and response cycles
  • Rate limits, timeouts and retry behaviour

How it works

A clear path from brief to sign-off.

No black boxes. You know what we are testing, what we found, and what it means for the business.

01

Map the surface

We inventory every endpoint, dependency and integration your product relies on.

02

Validate contracts

We test each endpoint against its specification, including schema, status codes and payloads.

03

Break it deliberately

We simulate failing dependencies, malformed input and expired credentials to see how your system degrades.

04

Automate the suite

Critical checks are automated so integration breakages surface on every deploy, not in production.

Proof

1B+
transactions daily behind APIs we have tested
25+
products tested end to end
9.7/10
average client satisfaction

Kare

API and integration testing across clinical workflows where accurate data exchange is a matter of care.

Read the case study

What you get

Evidence you can act on.

Endpoint coverage report Every endpoint tested, with pass, fail and risk notes.
Integration risk log Where third-party failures could cascade into user-facing problems.
Reusable API suite An automated collection your team can run in CI from day one.

How to engage

Start small or embed us fully.

Scoped project Start here A defined piece of work with clear objectives and a fixed deliverable. Typical start: within days
Ongoing retainer Continuous coverage across every release cycle, with consistent reporting. Monthly, rolling
Embedded tester A QA professional inside your team, on your tools and sprint cadence. Matched to your budget

FAQ

API Testing, answered.

Still unsure whether this is the right fit? Ask us directly.

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Do you test third-party APIs we do not control?

Yes. We cannot fix a partner’s API, but we test how your product behaves when theirs is slow, wrong or unavailable, which is where most real damage happens.

Can you work from our API documentation alone?

We can start there, but we validate the documentation against actual behaviour. Gaps between the two are often the first defects we report.

Will you leave us an automated suite?

Yes. Critical endpoint checks are automated and handed over so they run in your pipeline after we finish.

Often paired with this

Functional Testing Security Checks Performance Testing Test Automation Risk & Compliance ProcessCraft QA Talent Outsourcing

Ready to put api testing to work on your product?

Tell us what you are building and we will scope the right engagement for your stage and goals.

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