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- Tasks: Build and improve backend systems for advanced AI research using FastAPI.
- Company: Innovative tech company focused on impactful AI solutions.
- Benefits: Competitive salary, benefits, and opportunities for professional growth.
- Why this job: Make a real impact in AI development while working closely with stakeholders.
- Qualifications: 5+ years of backend engineering experience and a passion for code quality.
- Other info: Dynamic role with high expectations and excellent career-defining opportunities.
The predicted salary is between 100800 - 134400 £ per year.
This is an exceptional individual contributor role for engineers who want to work on problems that actually matter and be in an environment where you're not the smartest person in the room.
You will be building backend systems that support advanced AI research and deployment decisions. The software you work on influences how complex models are tested, understood, and monitored before they reach the real world. This is serious engineering in a fast moving space, with high expectations around quality, reliability, and judgement.
What you will work on:
- Building and improving backend systems used by internal teams every day using FastAPI
- Working on tools that operate at scale and need to be both fast and dependable
- Helping shape how new systems are designed and brought into production
- Collaborating closely with technical stakeholders to solve ambiguous problems
- Taking real ownership over the software you build
Most of the work is Python, but this is not scripting. You will be designing systems that need to be correct, reliable, and maintainable under real load.
What makes this role different:
- You are close to the problem, not buried under layers of abstraction
- You work directly with stakeholders, researchers and influence how tools are designed
- You will own features end to end, from idea through to production use
- Engineering standards are high, but speed still matters
- This is a role where judgement counts more than dogma
What they are looking for:
- Backend engineers who enjoy complexity and responsibility and have at least 5 years+ experience
- People who care about code quality but know when to move quickly
- Engineers who think in systems, not just features
- Experience with or an interest in LLMs
- Those motivated by the impact of AI and how it is developed
- Experience with LLMs, agents, cloud platforms, or security is a bonus, not a requirement.
This is a career defining role for someone who wants to stay deeply technical and work on problems that will only become more important over the next decade.
Principal Software Engineer in London employer: SR2 REC LTD
Contact Detail:
SR2 REC LTD Recruiting Team
StudySmarter Expert Advice 🤫
We think this is how you could land Principal Software Engineer in London
✨Tip Number 1
Network like a pro! Reach out to folks in your industry on LinkedIn or at meetups. We all know that sometimes it’s not just what you know, but who you know that can get you in the door.
✨Tip Number 2
Prepare for those technical interviews! Brush up on your Python skills and be ready to discuss your past projects in detail. We want to see how you think and solve problems, so practice explaining your thought process.
✨Tip Number 3
Showcase your passion for AI and backend systems! When you get the chance to chat with potential employers, let them know why you care about the impact of AI and how you can contribute to their mission. We love seeing enthusiasm!
✨Tip Number 4
Don’t forget to apply through our website! It’s the best way to ensure your application gets seen by the right people. Plus, we’re always looking for talented engineers who are ready to take ownership of their work.
We think you need these skills to ace Principal Software Engineer in London
Some tips for your application 🫡
Show Your Passion for Engineering: When writing your application, let us see your enthusiasm for backend systems and AI. Share specific examples of projects you've worked on that demonstrate your skills and how they relate to the role.
Be Clear and Concise: We appreciate clarity! Make sure your application is easy to read and straight to the point. Highlight your experience with Python and any relevant technologies without unnecessary fluff.
Tailor Your Application: Don’t just send a generic application. Tailor it to reflect how your experience aligns with our needs, especially around building reliable systems and collaborating with stakeholders. Show us you understand what we’re looking for!
Apply Through Our Website: We encourage you to apply through our website for the best chance of being noticed. It’s the easiest way for us to keep track of your application and ensure it gets the attention it deserves!
How to prepare for a job interview at SR2 REC LTD
✨Know Your Tech Inside Out
Make sure you’re well-versed in Python and backend systems, especially FastAPI. Brush up on your understanding of how complex models are tested and monitored, as this will be crucial in demonstrating your technical expertise during the interview.
✨Showcase Your Problem-Solving Skills
Prepare to discuss specific examples where you've tackled ambiguous problems. Think about times when you collaborated with stakeholders to design systems or features, and be ready to explain your thought process and the impact of your decisions.
✨Emphasise Quality and Speed
Highlight your experience balancing code quality with the need for speed. Be prepared to discuss how you ensure reliability and maintainability under load while still delivering features quickly. This will show that you understand the high expectations of the role.
✨Demonstrate Ownership and Impact
Talk about projects where you took full ownership from idea to production. Share how your contributions made a difference, especially in terms of AI development or backend system improvements. This will resonate well with their focus on impactful engineering.
