At a Glance
- Tasks: Lead the design and delivery of innovative AI solutions that transform financial controls.
- Company: Join Xelix, a fast-paced scale-up redefining automation in finance.
- Benefits: Enjoy a competitive salary, hybrid work, generous leave, and personal development budget.
- Other info: Dynamic environment with a focus on growth, fun, and team celebrations.
- Why this job: Shape the future of AI while working with cutting-edge technology and a talented team.
- Qualifications: 5+ years in AI/ML systems with strong system design and leadership skills.
The predicted salary is between 80000 - 90000 £ per year.
About us
At Xelix, we work with some of the world’s largest companies to automate and strengthen their financial controls. Our AI solutions redefine how Accounts Payable teams operate – moving from manual processes to automated, intelligent workflows. Xelix is a fast-paced scale-up – things move fast and expectations are high. We raised our Series B with Insight Partners in June 2025 and are expanding aggressively. We have a team of 150 talented people pulling together to achieve our goals. Everyone is trusted to take ownership, move fast and have a meaningful impact. We prioritise personal and professional growth, keep things fun, and love to celebrate a milestone together. In this role you’ll grow, be challenged and help shape the future of Xelix. If you’re excited about building something special with us, we’d love to hear from you.
About the role
We are hiring a Senior AI Engineer to help shape our AI systems and technical direction. You’ll lead the design and delivery of complex, production-grade AI solutions — combining machine learning, LLMs, and robust engineering practices to build high-impact products. We are a team of builders, focused on systems that work reliably in production, not just prototypes. We use modern AI tools extensively, enabling engineers to operate at a higher level – focusing on architecture, system design, and delivering meaningful product impact.
What you’ll be doing
- System Design & Ownership: design and lead end-to-end AI systems, from problem framing through to production deployment and iteration.
- Advanced AI Systems & Agents: architect complex agent-based workflows, tool ecosystems, and multi-step reasoning systems.
- Model Strategy: make decisions on model selection, fine-tuning, and when to use ML vs LLM vs hybrid approaches.
- Evaluation & Quality: define evaluation frameworks, metrics, and feedback loops to ensure reliability and continuous improvement.
- Production Excellence: ensure systems are scalable, observable, and robust in real-world environments.
- Technical Leadership: mentor other engineers, review designs, and raise the bar for engineering and AI practices across the team.
- AI-Assisted Engineering: drive effective use of AI tooling within the team, improving productivity without compromising quality.
- Cross-Functional Impact: work closely with product and leadership to shape what we build and why.
What you’ll bring
- Experience: 5+ years building and deploying ML or AI systems, with significant experience in production environments.
- Strong System Design Skills: ability to design end-to-end AI systems and make sound architectural decisions.
- Deep AI Expertise: strong experience with LLM systems (agents, tool use, evals) and/or traditional ML where appropriate.
- Pragmatism: ability to choose the right approach for the problem, balancing complexity, performance, and cost.
- Evaluation Mindset: experience designing and using evals to drive system improvements.
- Engineering Excellence: high standards for code quality, testing, and maintainability.
- Leadership & Mentorship: experience guiding other engineers and influencing technical direction.
- AI-Native Workflow: strong ability to leverage AI-assisted development tools effectively and thoughtfully.
What we offer in return
- Competitive salary of £80,000 to £90,000 depending on experience
- 27 days of annual leave (including 3 days Christmas closing) which increases up to 3 days based on tenure, with the option to roll over, buy or sell up to 3 days
- Hybrid working with two days a week from our dog-friendly Hoxton office
- On-site gym and cycle to work scheme
- Employee discount at over 100 retailers
- Comprehensive private medical & dental cover with Vitality
- Enhanced parental leave pay
- Learning & development culture – £1,000 personal annual budget
- We’re carbon-neutral and are working towards ambitious carbon reduction goals
- Lots of team socials & activities
- Annual team retreat
Want to learn more?
We believe that people from diverse backgrounds, with different identities and experiences make our company and product better. No matter your background, we’d love to hear from you! And if you have a disability, please let us know if there’s any way we can make the interview process better for you - we’re happy to accommodate!
This is a full-time position, with standard working hours from 9:00 AM to 6:00 PM, Monday through Friday.
Interview Process
While the exact process may vary slightly depending on the role, our typical interview stages are:
- Introductory Call – A short Teams conversation with a Talent Partner to discuss your background and the opportunity.
- Hiring Manager Interview – A 30–45 minute Teams meeting to explore your experience and fit for the team.
- Technical Task or Presentation – A role-relevant exercise to demonstrate your skills and approach.
- Final On-site Interview – An in-person meeting with our senior leadership team and co-founders at our office.
We strive to make the process clear, efficient, and respectful of your time.
Senior AI Engineer in London employer: Xelix
Xelix is an exceptional employer that fosters a dynamic and collaborative work culture, perfect for those looking to excel in the fast-paced world of enterprise SaaS sales. With a competitive salary and hybrid working options, employees benefit from a supportive environment that encourages professional growth and development. Located in Greater London, Xelix offers unique opportunities to engage with industry leaders while building meaningful relationships and closing impactful deals.
StudySmarter Expert Advice🤫
We think this is how you could land Senior AI Engineer in London
✨Tip Number 1
Network like a pro! Reach out to folks in your industry on LinkedIn or at meetups. A friendly chat can open doors that a CV just can't.
✨Tip Number 2
Prepare for those interviews! Research Xelix, understand their AI solutions, and think about how your experience aligns with their goals. Show them you’re not just another candidate.
✨Tip Number 3
Practice makes perfect! Do mock interviews with friends or use online platforms. The more comfortable you are talking about your skills, the better you'll perform.
✨Tip Number 4
Apply through our website! It’s the best way to ensure your application gets seen. Plus, it shows you’re genuinely interested in being part of our team.
We think you need these skills to ace Senior AI Engineer in London
Some tips for your application 🫡
Show Your Passion:When writing your application, let your enthusiasm for AI and engineering shine through. We want to see that you’re genuinely excited about the role and how you can contribute to our mission at Xelix.
Tailor Your CV:Make sure your CV is tailored to highlight your experience with AI systems and production environments. We love seeing specific examples of your work, so don’t hold back on showcasing your achievements!
Be Clear and Concise:Keep your application clear and to the point. We appreciate well-structured applications that make it easy for us to see your qualifications and fit for the role. Avoid jargon unless it’s relevant to the position.
Apply Through Our Website:We encourage you to apply directly through our website. It’s the best way for us to receive your application and ensures you’re considered for the role. Plus, it’s super easy!
How to prepare for a job interview at Xelix
✨Know Your AI Stuff
Make sure you brush up on your knowledge of machine learning and LLMs. Be ready to discuss specific projects you've worked on, the challenges you faced, and how you overcame them. This role is all about building reliable systems, so show them you know your stuff!
✨Showcase Your System Design Skills
Prepare to talk about your experience in designing end-to-end AI systems. Think of examples where you framed problems, made architectural decisions, and led projects from concept to production. They want to see your thought process, so be clear and confident!
✨Demonstrate Leadership and Mentorship
Since this role involves mentoring other engineers, be ready to share your experiences in guiding teams. Discuss how you've influenced technical direction and raised standards in previous roles. They’re looking for someone who can inspire others, so highlight your leadership skills!
✨Be Ready for Technical Challenges
Expect a technical task or presentation as part of the interview process. Practice explaining your approach to problem-solving and decision-making in AI projects. Make sure you can articulate your evaluation frameworks and how you ensure quality in your work. Confidence is key!
