Principal Full Stack Engineer - Full or Part Time

About us

You've probably heard of Autotrader, but do you know what we're all about?

We're the most trusted, most visited automotive marketplace in the UK. A heritage brand and a tech innovator. We bring together vehicle buyers and sellers to give them real choices. Cars may be what we're best known for but we’re also the place for pretty much everything else on wheels, from e-bikes to caravans.

In the automotive world, change is a constant, that’s why we take our job of untangling the complex car-buying journey very seriously.

At our core, we’re all about people. We go our own way while embracing diversity and celebrating our differences. We dedicate ourselves to the idea that we work better together.

Autotrader is a beautiful, surprising and vibrant place to work. We might not be for everyone, but we could be perfect for you.

About the job

We’re looking for Principal Full Stack Engineers to join us! Our technology teams combine a diverse set of technologies to meet the needs of our users, handling millions of requests a day across over 600 systems. We build these systems with industry standard frameworks and tools, such as React and Angular on the front end and Java, Spring Boot, Cloud SQL and Apache Kafka on the back end. All of this runs on our cutting edge cloud delivery platform, facilitating over 60k releases to production a year.

We’re a close-knit tech community where collaboration and knowledge sharing are at the core of what we do. Regular pair programming, code reviews, and stand-ups ensure that our engineers stay connected and aligned. As a Principal Engineer, you’ll play a visible, strategic role in driving system design and architecture decisions, mentoring team members, and helping our teams deliver high-quality solutions at scale. We actively encourage AI-assisted workflows. Whether it's using GitHub Copilot to eliminate boilerplate or LLMs to bounce ideas around, we give you the tools to move faster and focus on the hard engineering problems.

You might think that "Autotrader" means we’re looking for car enthusiasts, but that’s not the case. We’re looking for people who are passionate about technology, thrive in a collaborative environment, and have a genuine curiosity about solving complex problems.

What we’re looking for:

• Strong experience working across the stack, from designing scalable back-end systems to developing responsive front-end applications
• You should be comfortable working with Java, Spring Boot and the Java ecosystem / JVM
• Ability to architect and design complex, distributed systems that are scalable, maintainable, and performant
• Experience with modern front-end technologies (e.g., React or Angular, TypeScript/Modern JavaScript), along with proficiency in building RESTful APIs and web services.
• Strong knowledge of relational databases (SQL), along with experience working with document-based storage solutions (e.g., MongoDB)
• A structured approach to development and testing (including Test-Driven Development) with a focus on continuous delivery and automation
• Proven experience leading and mentoring teams, helping others grow technically while delivering high-impact projects

Although not a requirement, helpful experience includes:

• An interest in working with data at scale using tools like dbt, Spark, and AI/ML frameworks (e.g. PyTorch, TensorFlow, scikit-learn)
• Experience with Kafka or other event-driven architectures.

During our application process, you will be asked two questions to help us learn more about you and how you align with our values. These will be used as part of our selection criteria, to determine if we progress your application further

Benefits

We’re offering a salary of £60,000 – £80,000, plus an additional 10% of your salary awarded to you in shares each year. These awarded shares will become yours in yearly instalments over the next three years, and you can choose to either sell them or keep them as shares.

You'll have 28 days holiday per year, and that's in addition to bank holidays and half day closures on Christmas and New Year's Eve.

That’s not all. You'll be enrolled in our pension scheme, where our standard contributions are 7% and employee contributions are 5%. We also have comprehensive private medical cover, enhanced family leave provisions, a car salary sacrifice scheme, share-save options, and much more.

We always want to give you the support you need and help prioritise your wellbeing, that’s why we provide access to a Digital GP service, as well as specialist support for assisted fertility, gender dysphoria, menopause, period care plans and lots more.

On top of all that, our hybrid model, Connected Working, combines the best of both worlds – office and home working. You'll spend a minimum of 3 days a week in the office with your team, focused on collaboration and connection.

Additionally, we have our remote-first periods at set times during summer and winter. During these periods, you can work remotely anywhere in the UK and from certain locations abroad.

Alongside a wide range of benefits, we'll help you settle in with confidence from day one. If you're successful, one of the first things you'll experience is our tailored new-starter induction programme, Great Start, designed to help you feel welcome, connected, and set up for success.

Discover more about our hiring process and explore our Engineering Blog.