Senior Backend Engineer, Portfolio team (Python)

About InvestEngine We're a London-based fintech on a mission to make ETF investing simple and accessible. Over 150,000 clients have trusted us with over £3.5 billion in assets — and we're just getting started. We've been featured by MoneyWeek, Finder and Forbes, and we're growing fast with big ambitions. About the Role We're looking for a Senior Backend Engineer to join our Portfolio Team and help build the core investment products our clients use every day. The team owns portfolio creation, Managed Portfolios and related portfolio operations. This is product development work: you'll turn product ideas into reliable, well-built backend features that directly shape how clients invest. You'll write high-quality code, raise the bar through thoughtful code reviews, contribute to architecture and lead projects from requirements to production. You'll work closely with Product, frontend, QA, mobile and design in a small, autonomous team with a clear roadmap. What You'll Do Design, develop and maintain backend services in Python 3.11 using Django / DRF Build features for portfolio creation, Managed Portfolios and portfolio operations Lead roadmap projects end-to-end: clarify requirements with Product, propose the technical design, break down the work and ship it Design and build RESTful APIs used by our web and mobile apps Give constructive, high-quality code reviews and help raise the team's engineering standards Take part in architecture discussions and contribute to technical decisions Work with MySQL and Redis Identify and reduce technical debt Collaborate closely with Product, frontend, QA, mobile and design Contribute to the evolution of our architecture and engineering practices What We're Looking For 5+ years of experience in backend development Strong Python skills and solid software engineering fundamentals A good understanding of software architecture and service design Solid experience with relational databases and REST API design A track record of writing clean, maintainable, well-tested code Experience leading projects or features from idea to production The ability to pick up new codebases and technologies quickly Strong ownership, organisation and a collaborative working style Familiarity with Git, CI/CD practices and modern engineering workflows Good written and spoken English Nice to Have Experience with Django or Django REST Framework (not required, since strong fundamentals matter more than an exact framework match) Experience in fintech, investing, wealth management or another regulated industry Familiarity with AWS and Docker Experience with RabbitMQ, Kafka or other message brokers Experience using AI-assisted development tools in your daily work Contributions to open source or personal side projects How We Work We're a lean, collaborative team where engineers have real influence on architecture, technical decisions and engineering culture. The Portfolio Team is strong and autonomous. We work in two-week sprints with Product involved throughout, and we have a clear 3–6 month roadmap. You'll have the freedom to make technical decisions and own meaningful parts of the product without micromanagement or unnecessary bureaucracy. What We Offer Impact from day one: work on core investment products used by more than 150,000 clients Ownership: lead projects and become the go-to backend owner for key areas of the Portfolio domain Technical growth: influence architecture and technical decisions Modern tech stack: Python 3.11, Django, MySQL, Redis, AWS, GitHub, TeamCity Remote-first and flexible: work from anywhere, at your own pace Unlimited vacation: take time off when you need it, with no fixed limits Supportive team: thoughtful, skilled colleagues who care about quality and results Hiring Process HR interview Technical interview with the Backend team Conversation with the Portfolio team leadership Gamified cognitive assessment to understand how you think and solve problems