Senior Software Engineer in Test

Job Title: Senior Software Engineer in Test
Type: Inside IR35 Contract
Rate: £600-£650 per day
Duration: 6 months minimum (likely to extend)
Location: London - 3 days on site (Canary Wharf) 

A large fintech business are looking for a senior-level quality engineer with a strong software engineering mindset to help shape and safeguard new platform capabilities across complex workflow-driven systems on a contract-basis. This role sits embedded within product engineering, operating in a shared ownership model alongside Java and React developers, with a heavy emphasis on automation.
What you’ll be doing

Building and maintaining automated coverage across the stack, from APIs through to user journeys, using established internal tooling and frameworks.
Evolving existing test frameworks where required, while staying aligned with core engineering standards.
Working closely with frontend and backend engineers to ensure critical paths are well understood, well tested, and production-ready.
Participating in code and design discussions with a quality-first lens across the full delivery lifecycle.
Applying targeted exploratory testing early, where automation is still catching up with new functionality.
Ensuring automated testing is a first-class citizen within CI/CD, enabling fast and reliable releases.
Validating business-critical workflows within post-trade / collateral-style domains, where correctness really matters.What we expect

A solid engineering foundation, backed by significant hands-on experience in test automation.
Deep familiarity with Java or JavaScript/TypeScript-based automation, including modern UI and API testing approaches.
Comfort working across React-based front ends, RESTful services, and distributed architectures
Experience of testing microservices 
Experience operating in environments without a dedicated QA function, where quality is owned collectively.
Strong problem-solving skills and the ability to communicate clearly with engineers and stakeholders alike.Bonus points for

Exposure to cloud-native platforms (particularly AWS).
Working knowledge of containerised environments.
Experience with performance or resilience testing.
Familiarity with workflow engines, event-driven systems, or highly distributed platforms
Please note that you must be located in/around London and have UK right to work to be considered for this position - thank you