Backend API QA Engineer: Test, Automate, & Scale

Jobtailor; England; On-site; GBP 55,000 - 75,000; Full time

Job summary

Jobtailor in the United Kingdom is seeking an experienced backend/API test engineer to design, execute, and maintain test suites for GraphQL and REST APIs. You will verify payload structures, statuses, and response times, and integrate tests into CI/CD.

The role emphasizes data integrity, performance testing, and security assessments, with collaboration across Developers and DevOps in an autonomous agile team. Experience in TypeScript or Python test frameworks, and Docker, will be valued.

Qualifications

• 2+ years of dedicated software testing experience focused on backend architecture, API testing, and data integrity
• Hands-on experience with Postman, REST Assured, or Insomnia
• Experience querying PostgreSQL, MySQL, MongoDB, or DynamoDB
• Ability to write and maintain backend test suites in TypeScript or Python
• Working knowledge of Docker containerization
• Familiarity with CI/CD pipelines such as GitHub Actions or GitLab CI
• Excellent root-cause analysis skills
• Strong technical communication
• Proactive approach to identifying risks and edge cases
• Desirable: performance and load testing experience with k6, JMeter, Locust, or Gatling
• Desirable: familiarity with Kafka, RabbitMQ, and distributed microservices
• Desirable: understanding of OWASP and NIST 2.0 CSF
• Desirable: experience in retail, e-commerce, or fast-paced digital operations

Responsibilities

• Design, execute, and maintain test suites for GraphQL and REST APIs
• Verify API payload structures, status codes, and response times
• Build and maintain automated backend test frameworks in TypeScript or Python
• Integrate automated end-to-end test runs into CI/CD pipelines
• Write complex SQL/NoSQL queries to verify data flow, migration scripts, and backend consistency
• Test distributed microservices and asynchronous workflows such as Kafka, RabbitMQ, and Pub/Sub
• Conduct performance and load testing
• Assess backend security against OWASP API Top 10 guidelines and verify JWT/OAuth authentication
• Use tracing tools and log analysis to isolate complex breakpoints
• Collaborate with Developers and DevOps on root-cause fixes
• Participate in an autonomous agile team, prepare test scenarios, support continuous testing, and advocate for quality in planning and architecture discussions

Skills

API Testing

Automated Testing Frameworks

SQL/NoSQL Querying

Performance Testing

Root-Cause Analysis

Technical Communication

Proactive Risk Identification

Tools

Postman

REST Assured

Insomnia

Docker

GitHub Actions

GitLab CI

Kafka

RabbitMQ

Pub/Sub

K6

JMeter

Job description

Jobtailor in the United Kingdom is seeking an experienced backend/API test engineer to design, execute, and maintain test suites for GraphQL and REST APIs. You will verify payload structures, statuses, and response times, and integrate tests into CI/CD.

The role emphasizes data integrity, performance testing, and security assessments, with collaboration across Developers and DevOps in an autonomous agile team. Experience in TypeScript or Python test frameworks, and Docker, will be valued.