Senior Engineer (MongoDB) in London

We are looking for a highly skilled Senior Software Engineer to play a critical role in designing, building, and evolving our cloud‑native platforms. You will bring deep technical expertise, strong engineering judgement, and a customer‑first mindset to deliver secure, scalable, and high‑performing software. As a senior member of the team, you will help shape technical direction, reduce complexity and technical debt, and continuously improve how we engineer, deliver, and operate our services. This role has a strong emphasis on AWS serverless technologies and MongoDB, operating within a modern, Agile engineering environment.

Responsibilities

• Owning the design and delivery of high‑quality software solutions, working end‑to‑end across features, services, and systems to deliver meaningful customer and business outcomes.
• Building and operating cloud‑native, serverless applications on AWS, ensuring solutions are secure, resilient, scalable, and optimised for performance and cost.
• Leading by example in applying clean code, sound architectural principles, and engineering best practices that align with Legal & General’s SSDLC and technology strategy.
• Actively identifying, prioritising, and addressing technical debt, ensuring long‑term maintainability, reliability, and operability of our platforms.
• Defining and influencing test strategies that raise the quality bar, with a strong focus on security, accessibility, usability, resilience, and non‑functional requirements.
• Performing and leading high‑quality code reviews, providing constructive feedback that improves code quality, system design, and team capability.
• Driving continuous improvement in team processes, tooling, and ways of working, fostering a culture of learning, accountability, and technical excellence.
• Mentoring and coaching engineers within the team, supporting their technical growth while encouraging collaboration, inclusion, and knowledge sharing.
• Keeping pace with emerging cloud, data, and application technologies, identifying opportunities to adopt relevant advancements and sharing insights across the engineering community.
• Ensuring solutions and engineering practices consistently support fair customer outcomes, in line with Legal & General’s Customer Experience principles and Treating Customers Fairly policy.

Qualifications

• Strong expertise in modern software engineering, including clean code, clean architecture, design patterns, distributed systems, microservices, and cloud‑native application design.
• Proven experience delivering serverless solutions on AWS, with hands‑on use of services such as Lambda, API Gateway, ECS, and infrastructure‑as‑code using CloudFormation and serverless frameworks.
• Deep, practical experience with MongoDB, including schema design, performance optimisation, and advanced aggregation pipelines, alongside a solid understanding of SQL and other NoSQL data stores.
• Extensive experience building and maintaining large‑scale systems using TDD, automated testing, CI/CD pipelines, and containerisation, with a clear emphasis on reliability and operational excellence.
• A strong security‑first mindset, with real‑world experience in secure application development, web and API security, threat modelling, and compliance in cloud environments.
• Demonstrated ability to solve complex technical problems, make sound architectural decisions, navigate ambiguity, and balance immediate delivery needs with long‑term system health.
• Significant experience working in Agile environments (Scrum, Kanban), contributing to effective planning, prioritisation, dependency management, and continuous improvement across teams.
• A natural technical leader and communicator who can mentor others, facilitate technical discussions, collaborate effectively with non‑technical stakeholders, and positively influence team culture and outcomes.

Benefits

• The opportunity to participate in our annual, performance‑related bonus plan and valuable share schemes.
• Generous pension contribution.
• Life assurance.
• Healthcare Plan (permanent employees only).
• At least 25 days holiday, plus public holidays, 26 days after 2 years’ service. There’s also the option to buy and sell holiday.
• Competitive family leave.
• Participate in our electric car scheme, which offers employees the option to hire a brand‑new electric car through tax efficient salary sacrifice (permanent employees only).
• There are the many discounts we offer – both for our own products and at a range of high street stores and online.
• We’re creating net‑zero carbon workplaces by 2030 by investing in our sustainable, modern offices across the UK, all designed to bring people together and elevate the in‑person experience.