Senior QA/SDET

Senior QA / SDET | Java, Spring Boot & API Testing | London Hybrid | £60,000 + BonusI’m working with a specialist financial-services business looking to hire a backend-focused Senior QA Engineer / SDET to help drive quality across complex, business-critical trading systems.This is not a UI-heavy automation role.They are looking for someone who thinks like a developer and has strong experience testing backend services, APIs, microservices, databases and event-driven systems. You’ll take ownership of test strategy, build robust automation frameworks and help ensure reliability across highly integrated financial platforms.You’ll be joining a technical environment where accuracy, data integrity and production stability are essential.What you’ll be doing

• Driving the QA and automation strategy across backend trading and financial-services systems
• Building and maintaining automated API and service-level test frameworks using Java
• Testing Spring Boot applications, microservices and complex business logic
• Developing integration tests across APIs, databases, messaging systems and downstream services
• Mocking and stubbing external dependencies using tools such as WireMock, Mockito or MockServer
• Building deterministic test environments using TestContainers and Docker
• Validating asynchronous workflows, callbacks, retries, timeouts and failure scenarios
• Testing Kafka, RabbitMQ or other event-driven architectures
• Performing complex SQL validation, reconciliation and financial-data checks
• Implementing contract testing using Pact, Spring Cloud Contract or similar tools
• Embedding automated testing into CI/CD pipelines
• Supporting reliable releases across a regulated, business-critical environment
• Using Playwright or Selenium selectively for critical user journeys and smoke testingWhat they’re looking for
• Strong commercial experience as a QA Engineer, Automation Engineer or SDET
• A backend-focused testing background rather than predominantly UI automation
• Strong Java experience
• Good working knowledge of Spring Boot
• Strong experience with JUnit or TestNG
• Deep hands-on experience with REST Assured
• Strong API, service-level and integration-testing experience
• Experience using Mockito, WireMock or MockServer
• Experience with Spring Boot Test, including @SpringBootTest or @WebMvcTest
• Hands-on experience with TestContainers
• Strong SQL skills, including complex queries, joins and data validation
• Experience testing microservices and multi-system workflows
• Experience testing authentication flows such as OAuth2 and JWT
• Strong understanding of JSON schema validation
• Experience integrating automated tests into Jenkins, GitHub Actions or GitLab CI
• Docker experience and a basic understanding of Kubernetes
• Genuine practical experience with TDD, BDD, shift-left testing and the test pyramidHighly desirable
• Experience testing Kafka, RabbitMQ or other messaging systems
• Event, producer and consumer validation
• Avro or JSON schema validation
• Contract testing using Pact or Spring Cloud Contract
• Karate or Spring MockMvc
• gRPC or GraphQL testing
• Kotlin or Groovy
• Playwright or Selenium for limited UI coverageDomain experienceExperience within one or more of the following would be highly valuable:
• Trading systems or exchanges
• Risk platforms, including VaR, PnL or reporting systems
• Payments, banking or fintech
• Other complex regulated financial-services environmentsWhat success looks likeYou should be able to confidently explain how you would:
• Test a service that depends on several downstream APIs
• Mock services and simulate failures, delays and outages
• Test a payment or trading flow across multiple systems
• Validate APIs, databases and messaging together
• Test retries, timeouts, fallbacks and asynchronous processes
• Reconcile complex financial data using SQL
• Build stable, maintainable test frameworks rather than relying on manual Postman testingOffer
• £60,000 base salary
• Discretionary bonus
• Hybrid working - 3 days per week in the London office
• 25 days annual leave plus bank holidays
• Private healthcare with Vitality
• Gym membershipThis is a great fit for a backend-focused SDET who enjoys testing complex systems, writing production-quality automation code and working closely with developers to improve quality throughout the software development lifecycle.📩 Apply to hear more.