Our partner is looking for a Staff Full Stack Engineer - Sell Side Engine based in Spain.
The role combines deep backend and systems engineering with the flexibility to contribute to frontend development when needed.
You will make architecture-level decisions across integration-heavy systems, working with pricing, data, billing, and risk platforms. A major focus will be turning manual and error-prone commercial processes into scalable, automated products that can support new business categories.
Design and build the technical foundations connecting new-product initiatives with pricing, settlement, data, billing, and other core platforms.
Help develop and launch new product categories, contributing to the technical work required to bring new offerings from concept through production and qualified commercial pipeline.
Design deal-gating and risk-management tooling that enables the business to safely support new categories of commercial risk.
Build high-quality software across backend services and, when appropriate, contribute to React and TypeScript frontend development.




Write clean, maintainable, and well-tested code, participate actively in code reviews, and contribute to stronger engineering practices and documentation.
Deep technical expertise in backend engineering and systems design, with a proven track record of making architecture-level decisions for complex, integration-heavy systems.
Strong professional experience with Python and AWS serverless technologies, including Lambda, API Gateway, DynamoDB, and EventBridge.
Full Stack or Backend Engineering experience in a startup, scale-up, or fast-paced product environment, with ownership of complex projects from inception through delivery.
Demonstrated experience delivering projects where critical dependencies are owned by other teams, requiring strong collaboration and influence without direct authority.
Strong product mindset and ability to connect technical decisions to commercial outcomes and customer or busin

📌 Staff Full Stack Engineer (Madrid)
🏢 Lever
📍 Madrid