API testing services for REST and GraphQL APIs
BugsQA provides API testing services for REST and GraphQL APIs, validating endpoints, authentication, responses, business rules, data contracts, error handling, and integrations before backend defects reach web or mobile users.
API QA tests what happens behind the interface
API QA testing verifies that applications exchange the correct data, enforce the right rules, and respond properly to valid and invalid requests.
A frontend can look correct while the API behind it is:
- Returning incorrect data
- Accepting invalid requests
- Rejecting valid users
- Exposing the wrong information
- Breaking an integration
- Returning incorrect status codes
BugsQA tests the service layer directly so defects can be identified without waiting for the UI to expose them.
REST API testing
REST API testing validates endpoints, HTTP methods, status codes, request payloads, responses, authentication, and business behaviour.
Coverage can include:
- GET requests
- POST requests
- PUT and PATCH requests
- DELETE requests
- Status codes
- Headers
- JSON payloads
- Authentication
- Authorization
- Pagination
- Filtering
- Error responses
Testing should confirm both successful scenarios and failure conditions.
GraphQL testing
GraphQL testing verifies queries, mutations, authentication, schemas, errors, and returned data across the fields an application requests.
GraphQL allows clients to request specific data, which creates different testing concerns from traditional REST endpoints.
Testing can cover:
- Queries
- Mutations
- Variables
- Authentication
- Authorization
- Schema behaviour
- Required fields
- Error responses
- Data consistency
The goal is to confirm that the API returns the correct structure and business outcome for each request.
Authentication and authorization testing
API authentication testing verifies who can access an endpoint, while authorization testing checks what each authenticated user is allowed to do.
These are different concerns.
A user may successfully log in but still need restrictions based on:
- Role
- Account
- Subscription
- Organization
- Permission level
- Resource ownership
QA can verify that protected endpoints reject requests that should not be allowed and return expected data for authorized users.
Validate data contracts and responses
API contract testing checks whether response structures continue to match what web, mobile, and third-party consumers expect.
A backend change can technically return a successful status while breaking the frontend because:
- A field was renamed
- A data type changed
- A required property disappeared
- A response shape changed
- Null handling changed
Contract validation helps catch those breaking changes earlier.
For complete frontend coverage, API QA can work alongside our functional testing services.
Test error handling and edge cases
API functional testing should verify failure behaviour as carefully as successful requests.
Coverage can include:
- Invalid credentials
- Expired tokens
- Missing fields
- Invalid data types
- Duplicate records
- Unauthorized access
- Nonexistent resources
- Malformed requests
- Empty results
- Service failures
A useful API should return predictable errors that the consuming application can handle correctly.
Test third-party and internal integrations
API integration testing verifies that connected systems exchange the expected data and remain compatible across complete workflows.
Applications commonly depend on integrations for:
- Payments
- Authentication
- Messaging
- Shipping
- Analytics
- CRM platforms
- External data
- Internal microservices
One service can work independently while the full integration still fails.
BugsQA tests the connection between services, not just each endpoint in isolation.
Postman and automated API testing
Postman API testing can organize requests, environments, assertions, and repeatable API workflows for manual and automated validation.
Collections can help teams test:
- Endpoint behaviour
- Authentication
- Data
- Status codes
- Error conditions
- End-to-end API sequences
For new Postman CI workflows, Postman currently recommends the Postman CLI.
Newman can still run existing Postman collections in legacy workflows, but Postman now states that Newman is no longer maintained for its newest collection format.
BugsQA selects the appropriate approach based on the client’s current Postman environment and CI setup.
API testing in CI/CD
Automated API testing can run during development and deployment so backend failures are detected before they reach the user interface.
API tests can run:
- On pull requests
- After backend deployments
- Before releases
- During scheduled regression
- After integration changes
- As part of smoke testing
Because API tests do not always need a browser, they can provide fast feedback around backend behaviour.
Need API QA before your next release?
Validate backend changes, REST endpoints, GraphQL services, authentication, and integrations before frontend users discover the failure.
Our API testing process
BugsQA turns API requirements and documentation into structured endpoint coverage, reproducible defects, regression checks, and clear results.
- 01
Map the APIs
We identify REST or GraphQL services, environments, consumers, integrations, and critical workflows.
- 02
Define coverage
We prioritize: endpoints, authentication, business rules, data contracts, error conditions, and integrations.
- 03
Execute API tests
We validate requests, responses, data, status codes, and expected outcomes.
- 04
Report defects
Reports can include: endpoint, request, payload, response, status code, expected result, actual result, and environment.
- 05
Retest fixes
Corrected API behaviour and connected workflows are verified.
- 06
Build regression coverage
Stable high-value API scenarios can be automated for repeated execution.
What you receive from API testing
API QA deliverables give developers clear information about endpoint behaviour, failures, integrations, and regression risk.
Depending on scope, BugsQA can provide:
- API test plan
- Endpoints, environments, priorities, authentication flows, and testing scope.
- API test cases
- Positive, negative, integration, and edge-case scenarios.
- Defect reports
- Reproducible request and response evidence.
- API collections
- Organized requests and assertions where Postman or compatible tooling is appropriate.
- Regression results
- Pass and fail status across repeated API scenarios.
- Automated API coverage
- Repeatable tests that can run as part of development or release workflows.
API testing for web and mobile applications
API testing supports both web and mobile QA because many user-facing workflows depend on the same backend services.
A broken endpoint can affect:
- A website
- An iOS app
- An Android app
- Internal tools
- Third-party integrations
Testing the API directly can isolate whether a defect belongs to the frontend, backend, or connection between them.
Nearshore API QA for US teams
BugsQA provides nearshore API testing from Colombia for US engineering teams that need testers working alongside backend and frontend developers.
Shared working hours make it easier to review failed requests, clarify expected contracts, retest backend fixes, and validate connected frontend behaviour within the same release cycle.
More website testing services
What clients say about our testing
Reviews from our QA engineer’s Upwork profile, quoted as written.
5 out of 5 stars
“Great to work with. He knows testing very well and works efficiently.”
5 out of 5 stars
“Juan did a great job on this project. He always replied quickly and met every deadline, going above and beyond. He paid close attention to details improving the quality of the product and made sure customers were helped in the right way. His work was clear and well organized. I would be happy to work with him again in the future.”
Pricing
QA testing as a service that scales with your product
BugsQA provides QA testing as a service for product teams that need flexible testing capacity without building an entire internal QA department.
Choose the level of support that fits your product and release cycle.
Release QA
Best for launches, major updates and pre-release validation
Get focused QA coverage around a specific release, feature set, MVP, redesign, or migration.
Ideal for teams that need an independent quality pass before shipping.
From
$2,500
fixed price / project
- Test plan + test cases
- Manual functional & cross-browser/device testing
- Bug reports with video + severity
- Fix verification (1 retest round)
- Final QA sign-off report
Ongoing QA
Best for teams shipping every sprint
Add recurring manual, exploratory, regression, web, or mobile testing to your existing development cycle.
Ideal when developers are handling too much of their own QA or an internal tester needs additional capacity.
From
$4,200
per engineer / month
- A dedicated QA engineer from our team
- Works in your sprints, tools and time zone
- Regression testing every release
- Weekly QA reports
- Adjust the hours month to month
QA automation
Best once your core flows are stable
Automate the stable, repeatable checks your team runs every release, starting with the flows that matter most.
Ideal after manual coverage is in place and the same regression keeps repeating.
From
$6,500
setup, then monthly plan
- Smoke and regression checks for your critical flows
- Built on top of our manual test cases
- Runs in your CI/CD when you are ready
- Kept up to date as your product changes
All plans include: NDA on request, bug tracking in your Jira, US time-zone overlap and no long-term contract. [Confirm terms] Hourly testing also available: manual QA $25–35/hr, test automation $35–45/hr.
Free QA consultation
Get an API testing plan
Tell us what APIs support your product and where failures are creating risk.
What happens next:
- 1
We reply within [1 business day]
A QA lead reviews your request and asks about scope and platforms.
- 2
Free 30-minute QA consult
We map your app, risks and release schedule.
- 3
Proposal and test plan
You get a recommended mix of manual testing and automation, with a quote.
Email: hello@example.com
What is API testing?
API testing verifies backend services directly by checking requests, responses, authentication, data, business rules, and error handling.
Do you test REST APIs?
Yes. REST testing can cover endpoints, HTTP methods, status codes, payloads, authentication, and response data.
Do you test GraphQL APIs?
Yes. GraphQL testing can cover queries, mutations, variables, schemas, authentication, authorization, and returned data.
Can you use Postman?
Yes. Postman can be used to organize and execute API tests where it fits the project. For new CI workflows, the current Postman CLI is preferable to treating Newman as the default.
Can API tests run automatically?
Yes. Stable API tests can run inside CI/CD workflows, scheduled regression suites, or release checks.
Do you test third-party integrations?
Yes. API integration testing can validate connected systems and the workflows that depend on them.
Test the backend before the frontend has to expose the bug
A successful screen does not prove that the API behind it is correct.
BugsQA provides API testing services for REST and GraphQL applications, validating endpoints, authentication, data contracts, integrations, errors, and regression risk before backend defects reach users.