Can you test our API without access to the source code?

Yes. Black-box API testing needs only a test environment, credentials for each role and whatever documentation exists, ideally an OpenAPI spec or Postman collection. If there is no documentation, we build a collection from observed traffic and confirm expected behavior with your team.

Is API security testing the same as a penetration test?

No. Our API security tests are automated and repeatable checks against the OWASP API Top 10 that run on every build. A penetration test is a time-boxed manual assessment by specialist testers. Many teams need both, and our suites help keep fixes from a pentest in place.

How do you load test an API without hurting production?

We run load tests against a staging environment sized like production, or against production in an agreed low-traffic window with limits in place. Scenarios are built from real usage patterns, and k6 thresholds stop the test automatically if error rates climb past the agreed level.

Which tools will we be left with?

Everything runs on open or widely used tools: Postman and Newman, REST Assured, Pact and a Pact Broker, and k6 or JMeter, all configured in your repository and CI. There is no proprietary platform to license, so your team can keep running the tests after our engagement.

QA engineer working through test cases on a laptop

API quality for B2B products

API testing services for US software teams

For B2B products the API is the product for many customers. We test it the way integrators use it: functional automation, contract tests between services, security checks against the OWASP API Top 10, and load tests before traffic grows.

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About quality assurance

Functional API automation in your pipeline

We turn your OpenAPI spec or existing Postman collections into automated suites that check status codes, response schemas, business rules, pagination, filtering and error messages for every endpoint. Postman collections run in CI through Newman, and Java teams get REST Assured tests that sit next to their service code. GraphQL APIs are tested for queries, mutations and permission rules per field.

Suites run in GitHub Actions on every pull request against a disposable environment, with test data created and removed by the tests themselves, so a failing check points to a real change rather than a stale record. Each failure shows the request, the response and the assertion that broke, which is usually enough for a developer to fix it without asking us.

Contract testing between services and partners

When several teams or microservices depend on each other, end-to-end tests become slow and fragile. Consumer-driven contract tests with Pact let each consumer record what it expects from a provider, and the provider verifies those contracts in its own build. A breaking change fails before deployment instead of after, without spinning up the whole system.

For public APIs used by your customers, we also compare each release against the published OpenAPI spec and flag removed fields, changed types and new required parameters before they break someone's integration. Intentional breaking changes are then handled deliberately, with a new version, a deprecation date and a changelog entry your customers can plan around.

Security and performance checks

Security tests follow the OWASP API Security Top 10: broken object level authorization, broken authentication, excessive data exposure, missing rate limits and function level access control. We test with tokens for each role and tenant to confirm one customer cannot read another's data. Load tests in k6 or JMeter measure latency and error rates at agreed traffic levels and fail the build when thresholds are missed.

API testing we deliver

Automated REST API suites in Postman and Newman
REST Assured tests for Java and Spring services
GraphQL query, mutation and permission testing
Consumer-driven contract testing with Pact
OpenAPI spec validation and breaking change checks
Authorization and tenant isolation tests based on the OWASP API Top 10
Load and soak tests in k6 or JMeter with CI thresholds

Built for the market

What US API teams ask us to cover

Webhook delivery, retries and signature verification for partners
Tenant isolation tests for multi-customer B2B SaaS
Third-party APIs such as Stripe or QuickBooks stubbed in test runs
Evidence of API testing for your SOC 2 or customer security reviews
Results reported on the pull request, not in a separate tool nobody opens

Time zone: US Eastern time is nine to ten hours behind Lahore. A fixed overlap window in your morning is agreed at the start of the project, and the rest of the work happens overnight for you, so each day starts with progress to review.
Payments we integrate: Stripe, PayPal, Square, Authorize.Net, ACH bank transfers, Apple Pay
Tax and data: Built for US sales tax through providers such as Stripe Tax, Avalara or TaxJar. Personal data handled in line with the CCPA/CPRA and other US state privacy laws.
Language: English.

Guides

API testing guides for the United States.

QA outsourcing for US SaaS companies: a practical guideQA outsourcing for US SaaS companies: when it makes sense, engagement models, Playwright and Cypress automation, CI, overlap hours, access security and metrics.

Questions

API testing: common questions

API testing checks that an endpoint behaves correctly on its own: right data, right errors, right permissions. Contract testing checks that a provider still gives its consumers what they rely on. You need both once several services or customers depend on the same API.

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