Senior Technical Business Analyst (Contractors Outside IR35) - FINTECH / LONDON

WE ARE: At Adaptive, we are a financial consulting firm that partners with capital, commodity, and digital market participants. We value differentiation through technology. Our experienced teams design and deliver complex front-office technology solutions using our proven accelerators to create long-term competitive advantage. Our clients include the world's leading investment banks, investment managers, fintechs and capital market service providers. With a global reach with offices in London, New York, Manila, Barcelona and Montreal, we have a proven track record of delivering powerful, elegant and intuitive trading technology solutions. We are now looking for Technical Business Analyst services on an exciting project! THE INDIVIDUAL/S PROVIDING THE SERVICES WILL HAVE THE FOLLOWING EXPERIENCE: The ability to see the big picture while managing the finer details of delivery. The ability to communicate and facilitate effectively across both technical and business stakeholder groups. The ability to bring structure and clarity to ambiguous or complex delivery situations . The ability to understand system behaviour and interactions beyond purely functional outcomes . A strong technical and domain-driven mindset, with the ability to work closely with engineering teams Hands-on experience with high-performance messaging or sequencing platforms such as Aeron, Kafka, Hydra, or equivalent — including an understanding of message ordering, state machine replication, and fault-tolerant distributed systems Demonstrable exposure to low-latency or high-throughput messaging infrastructure in a financial or similarly demanding technical environment Experience in QA, Software Engineering, Technical Business Analysis, or another highly technical product environment A product-first mindset, combining Domain-Driven Design principles with a deep understanding of systems and user impact The ability to define and document functional and non-functional requirements clearly and effectively An understanding of performance, scalability, resilience, and availability in modern platforms Experience working in Agile or Kanban environments across the full software development lifecycle Demonstrable experience contributing to architecture and design discussions, simplifying complex challenges into deliverable solutions The ability to create process flows , sequencing diagrams, and documentation that align technical and operational teams DESCRIPTION OF THE SERVICES: DRIVE CLARITY IN COMPLEX ENVIRONMENTS: Shaping requirements and driving alignment in ambiguous situations, with minimal direction Adapting to different delivery models across products, including engineering-led and BA-led ways of working Define and maintain functional and non-functional requirements — including operational scenarios, acceptance criteria, and QA validation needs across distributed workflows Ensuring questions are raised early, so that solutions are well understood, well defined, and ready to be delivered SHAPE THE BACKLOG AND DELIVERY: Collaborate with engineering, QA, and architecture teams to translate complex technical solutions into structured backlog items, deliverable stories, and testable outcomes Help stakeholders make their vision for the product materialise, especially in the early stages of each delivery phase Be the stakeholders' proxy in the team — able to make quick, firm decisions on scope, requirements and prioritisation/triage Drive backlog review and estimation processes, and take part in planning activities Define acceptance criteria and tests up front as part of a Business-Driven Development approach Follow up during implementation and testing phases to ensure delivery satisfies requirements COLLABORATE ACROSS THE TEAM: Work closely with QA to assess failure scenarios and help distinguish bugs, enhancements, and new feature requirements Facilitate discussions across technical and business stakeholders to drive clarity, alignment, and sound decision-making Support…