Senior Algorithms Engineer (Python) – London

About the Position

We are seeking a Senior Algorithms Engineer (Python) to join our fintech team in London, working on complex optimization problems.

Our client is a fintech technology company building solutions that help global financial institutions unlock capital constraints and improve market efficiency. Their algorithms sit at the core of the product - solving complex optimization problems that impact trillions of dollars across capital markets each year. You will join a cross-office Algorithms team (New York & London), working on systems that are already in production while also contributing to new product development from the ground up.

Location: 11th Floor South, 69 Old Broad Street, London EC2M 1QS, UK

Work mode: Hybrid - 4 days in office, 1 day remote

Schedule: Monday–Friday, flexible 9-hour day

Responsibilities

• Partner with Product Owners and subject-matter experts (SMEs) to understand business requirements and deliver precise technical solutions
• Productionize, scale, and deploy complex financial optimization algorithms into enterprise-grade systems
• Research and iterate on existing optimization algorithms to continuously improve performance, speed, and scalability
• Conduct design and code reviews, ensuring solutions meet engineering standards and best practices
• Enhance CI/CD pipelines for financial algorithm development and deployment
• Contribute to the design of the company’s core product framework - validating approaches through documented designs and prototypes
• Provide algorithm domain expertise during live portfolio optimization events

Requirements

• Advanced knowledge of Python (3+ years production experience) with strong Object-Oriented Programming expertise
• Deep understanding of algorithms and data structures; demonstrated ability to design and implement them at scale (2+ years)
• Proven experience translating mathematical models into enterprise-level software solutions
• Strong experience in test-driven development (TDD) and agile delivery environments
• Demonstrated experience on quantitative or optimization-driven projects
• Ability to work through ambiguous, incomplete problem statements and drive solutions independently
• Strong critical thinking and scalability mindset - making systems run faster and handle larger loads
• Experience working across AWS and Python backend stacks
• Proficiency with AI-assisted development tools (e.g., Cursor, GitHub Copilot, Claude Code, or similar)
• Excellent communication skills with direct experience working alongside business stakeholders
• Advanced English (C1+)
• Bachelor’s degree in Computer Science, Mathematics, Operations Research, Financial Engineering, or a relevant quantitative field
• Self-driven with strong initiative - proactively raises issues and drives improvements
• Comfortable operating under ambiguity; able to progress without 100% task clarity
• Strong critical thinker with a passion for multi-dimensional mathematical problem-solving
• Collaborative team player effective across engineering, product, and business teams
• Ability to manage multiple priorities and deadlines simultaneously

Nice to Have

• Advanced degree in Computer Science, Mathematics, Operations Research, Financial Engineering, or related quantitative discipline
• Hands-on experience with optimization frameworks, especially Gurobi (highly desired); also NAG, OR-Tools
• Research or modeling experience in mathematical optimization or operations research
• Financial markets knowledge and/or experience with derivatives products, clearing, or margin calculation
• Experience with PostgreSQL and AWS
• Knowledge of derivatives clearing / margin calculation

We Offer

• Competitive salary
• Opportunity to work in a dynamic and innovative fintech environment
• Flexible working arrangements (Hybrid model)
• Professional growth and development opportunities
• Collaborative and supportive team environment

About the Company

Our client is a leading fintech technology company dedicated to building solutions that help global financial institutions unlock capital constraints and improve market efficiency. With a strong focus on innovation and excellence, they are at the forefront of developing cutting-edge algorithms that drive significant improvements in capital markets.