Product Engineer (Full-stack) in London

About Warden AI

AI is being deployed across every industry, transforming how decisions are made and how people interact with technology. But as adoption accelerates, so do concerns about bias, accuracy, and accountability. Warden AI safeguards this transformation by making sure AI systems are fair, transparent, accurate, and explainable. Founded in 2023 and backed by investors from Playfair, Monzo, Onfido, and Codat, our platform continuously audits AI models, delivering independent oversight through dashboards, reports, and certifications. With teams in London and Austin, we partner with both fast-growing platforms and global enterprises to enable the responsible adoption of AI worldwide.

About the role

We are hiring a Full-stack Product Engineer to help build and evolve the core product experiences of Warden’s AI assurance platform. The role spans frontend product development and backend services, turning complex analytical and audit workflows into clear, reliable software that customers can trust. You will join an existing engineering team and report to the CTO, working closely with product, data, and customer-facing teams. A strong candidate will bring a solid background in TypeScript and React, helping strengthen the team’s full-stack product development capabilities, particularly across TypeScript, React, and Next.js, while contributing to backend systems in Python. Your work will have visible impact on product quality, usability, and reliability across the platform. As one of our early product engineering hires, you will help shape how this role grows over time and take on more responsibility across product development as we scale.

What you’ll do

• Build end-to-end product features, e.g. design and implement new dashboards, workflows, and UI components that help customers understand and act on AI audit results.
• Lead on frontend experiences, e.g. develop polished, accessible interfaces, working closely with product and design to get details right.
• Contribute to backend services, e.g. extend services that power audits, reports, and internal tooling, and wire them cleanly into the frontend.
• Translate product requirements into working software, e.g. break down loosely defined problems, propose pragmatic solutions, and iterate quickly based on feedback.
• Improve product quality and reliability, e.g. fix bugs, reduce edge cases, improve performance, and strengthen type safety and test coverage.
• Collaborate cross-functionally, e.g. work closely with data scientists, solutions engineers, and founders to ship features that solve real customer problems.
• Continuously improve the codebase, e.g. refactor areas you touch, improve developer ergonomics, and contribute to shared patterns and conventions.

What you should bring

• A self-starting, get-it-done attitude. You’re comfortable with ambiguity, take ownership, and move from idea to working software without needing constant direction.
• Strong TypeScript and React experience. You’ve shipped real, user-facing features and care about code quality, usability, and maintainability. Experience with Next.js is a plus.
• Full-stack mindset. You’re happy working across the stack and don’t see frontend and backend as rigid silos.
• Experience shipping production software. You’ve worked on systems that real users depend on and understand the importance of reliability, performance, and maintainable code.
• Pragmatic trade-off decision making. You know when “good enough” is the right choice to move fast, and when to slow down to build something more robust.
• Product-oriented thinking. You care about usability, clarity, and customer impact, not just “getting something to work.”
• Startup mindset. You thrive in fast-paced, early-stage environments, are excited to wear multiple hats, navigate ambiguity, and bring structure where needed.
• Curious about AI, compliance, or HR Tech. Experience in any of these is a plus, but not required.

This role isn’t for you if…

• You’re looking for a frontend or UI engineering role. This is a product engineering role that involves reasoning about systems, data, and trade-offs across the stack.
• You have limited frontend product experience. Attention to detail and a strong focus on usability and customer experience are core parts of this role, not optional extras.
• You’re primarily interested in backend or infrastructure work. This role requires leading product experiences end-to-end, from backend logic and data flows through to the customer-facing UI.
• You need very detailed specifications before starting work. You’ll often help shape solutions rather than just implement them.
• You don’t enjoy collaborating closely with non-engineers. Product, data, and customer context are core to the role.
• You prefer highly mature processes and tooling. We’re still building many of these, and you’ll be helping shape them as we grow.
• You want a narrow, fixed remit. Priorities shift, and we focus on the highest-impact work, even when it’s not squarely within a defined role.

What we offer

• £70-90k base salary + meaningful equity in rapidly growing business
• 33 days holiday (incl. bank holidays)
• Hybrid working model (we spend 3 days/week in our London office)
• Learning and Development budget of £500 per year

Interview process

Our interview process involves the following stages:

• Initial screen (40min) - Intro with our CTO to align on your background and the role.
• Founder screen (30min) - Conversation with our CEO about how you operate in an early-stage startup and a customer- and sales-facing environment.
• Technical assessment (30min) - A short task to confirm technical proficiency.
• On-site interview (60min) - Final interview including a collaboration exercise.
• Reference checks & Offer - We move quickly from references to a clear offer. Our average process takes around 2-3 weeks, but we will always work around your availability.

If you have any specific questions or want to talk through reasonable adjustments ahead of or during application please contact us at any point.

Equal opportunities for everyone

Diversity and inclusion are a priority for us, and we are making sure we have lots of support for all of our people to grow at Warden AI. We embrace diversity in all of its forms and create an inclusive environment for all people to do the best work of their lives with us. This is integral to our mission of supporting the responsible adoption of AI systems. We’re an equal-opportunity employer. All applicants will be considered for employment without attention to ethnicity, religion, sexual orientation, gender identity, family or parental status, national origin, veteran status, neurodiversity status or disability status.