Principal Software Development Engineer

Manchester Digital; London, Bristol, Manchester; Hybrid; GBP 60,000 - 100,000; Full time

Job description

We are a technology-driven company building high-performing, scalable, and resilient software solutions. Our teams work with a modern tech stack including .NET, MongoDB, AWS, Jenkins, SQL Server, and streaming technologies.

We’re looking for a hands-on Principal Engineer who can code, design scalable systems, manage Staff Engineers, and drive technical excellence across multiple teams. This role is perfect for a technical leader who still enjoys writing code while shaping architecture and mentoring engineers.

About the role

As a Principal Engineer, you will play a critical role in:

• Architecting scalable, high-performance systems
• Coding and reviewing mission-critical features (at least 60% hands-on)
• Managing and mentoring Staff Engineers & Senior Developers
• Driving best practices in software development and AI-powered engineering
• Owning non-functional requirements (NFRs) such as security, scalability, and reliability
• Optimising cloud infrastructure and CI/CD pipelines

If you thrive on solving complex technical challenges, leading by example, and empowering teams, this is the role for you!

Key responsibilities

• Hands-on coding (at least 60% of the time), working on core application components and system architecture
• Technical leadership – guiding multiple teams and ensuring best practices
• Managing & mentoring Staff Engineers – supporting career growth and technical excellence
• Architecting and scaling distributed systems and cloud-native applications
• Defining and enforcing non-functional requirements (NFRs) – scalability, security, performance
• Implementing Test-Driven Development (TDD) and automation best practices
• Optimising CI/CD pipelines with Jenkins & AWS
• Leading containerisation efforts with Docker & Kubernetes
• Collaborating with cross-functional teams to align technical solutions with business needs
• Researching and implementing AI-driven development tools to boost productivity

What we’re looking for

• Proven experience as a Principal Engineer / Lead Engineer / Software Architect
• Proven hands-on coding experience with .NET, SQL Server, MongoDB, Angular/NextJS, AWS, and streaming technologies
• Strong experience in building scalable and high-performance applications
• Strong experience managing Staff Engineers & Senior Developers
• Solid understanding of Test-Driven Development (TDD) and modern testing frameworks
• Experience with Docker & Kubernetes for containerisation and cloud deployment
• Strong knowledge of CI/CD pipelines, automation, and deployment best practices
• Experience with AI-assisted development tools is a plus
• Excellent leadership and communication skills – able to coach and influence team

About us

AJ Bell is one of the fastest-growing investment platform businesses in the UK offering an award-winning range of solutions that caters for everyone, from professional financial advisers to DIY investors with little to no experience. We have over 561,000 customers using our award-winning platform propositions to manage assets totalling more than £89.5 billion. Our customers trust us with their investments, and by continuously striving to make investing easier, we aim to help even more people take control of their financial futures.

Having listed on the Main Market of the London Stock Exchange in December 2018, AJ Bell is now a FTSE 250 company.

Headquartered in Manchester with offices in central London and Bristol, we now have over 1,500 employees and have been named one of the UK's 'Best 100 Companies to Work For’ for six consecutive years and in 2024 named a Great Place to Work.

At AJ Bell you can expect a friendly working environment with a strong sense of teamwork. We have a great sense of pride in what we do, and this is reflected in our guiding principles.

Our perks and benefits

• Starting holiday entitlement of 26 days, increasing up to 31 days with length of service plus a holiday buy and sell scheme
• A choice of pension schemes with matched contributions up to 7%
• Discretionary bonus scheme
• Annual free share awards scheme
• Buy As You Earn (BAYE) Scheme
• Health Cash Plan – provided by SimplyHealth
• Discounted private healthcare scheme and dental plan
• Free gym membership
• Employee Assistance Programme
• Sick pay+ pledge
• Enhanced maternity, paternity, and shared parental leave
• Loans for travel season tickets
• Charitable giving opportunities through salary sacrifice
• Calendar of social events, including monthly payday drinks, annual Christmas party, summer party and much more
• Ongoing technical training
• Peer recognition scheme, with rewards including restaurant and shopping vouchers or time off
• Monthly leadership breakfasts and lunches
• Casual dress code
• Access to a range of benefits from our sponsorship deals

At AJ Bell, our people are the heart of our culture. We believe in building strong connections by working together. That's why we offer a hybrid working model, where you’ll spend a minimum of 50% of your working time per month in the office. For new team members, an initial period will be full-time in the office to help you immerse yourself in our business and build valuable relationships with your colleagues.

AJ Bell is committed to providing an environment of mutual respect where equal employment opportunities are available to all applicants and all employees are empowered to bring their whole self to work.

We do not discriminate on the basis of race, sex, gender identity, sexual orientation, age, pregnancy, religion, physical and mental disability, marital status, and any other characteristics protected by the Equality Act 2010. All decisions to hire are based on qualifications, merit, and business need.

If you like the sound of the above, or just want to know more about the company and the role, we'd love to speak to you.