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- Tasks: Design and build robust backend systems using Python for a cutting-edge AI automation platform.
- Company: Join a recently funded Series A tech company focused on real-world AI solutions.
- Benefits: Competitive salary, meaningful equity, and a high ownership role with direct influence.
- Why this job: Make impactful decisions while tackling complex engineering challenges in a supportive team.
- Qualifications: Strong backend experience, deep Python skills, and comfort in evolving product environments.
- Other info: Intellectually stimulating culture valuing quality, correctness, and clear communication.
The predicted salary is between 100000 - 160000 £ per year.
Location: London based - hybrid
Salary: £100,000 - £160,000 + equity
Tech Stack:
- Backend: Python (FastAPI)
- AWS
Are you a backend engineer who cares more about building robust systems than chasing AI hype? We are working with a recently funded Series A technology company building AI powered automation for real world, critical workflows. Their platform captures operational knowledge and turns it into production grade systems that AI can interact with safely and reliably. This is not applied machine learning, not foundation model development, and not experimental agent playgrounds. The work is focused on the engineering around AI: evaluation, control, reliability, and building systems that behave predictably in production. Engineers work closely with users, own problems end to end, and shape both the technical and product direction in a small, high trust team. It is an intellectually demanding environment where quality, correctness, and long term system design genuinely matter.
Responsibilities
- Design and build backend systems that power a complex, evolving platform using Python
- Own data models, schemas and database design with a strong focus on correctness and scale
- Build ingestion pipelines and integrations with production customer systems
- Develop tooling that enables AI capabilities while maintaining strong control and evaluation standards
- Work directly with customers to understand workflows and translate them into reliable systems
- Contribute to architectural decisions and long term platform evolution
Requirements for Success
- Strong experience as a backend or systems focused engineer
- Deep Python experience with excellent engineering fundamentals, or equivalent depth in a strongly typed language
- Strong SQL skills and experience designing schemas
- Experience building complex backend systems that evolve over time
- Comfort working in ambiguous, early stage product environments
- Experience with data ingestion pipelines or internal tooling for AI or data teams
The engineering team is currently small and senior, with a strong academic and systems background. There is no formal product team. Engineers own user experience, technical decisions and delivery. The culture values thinking time, technical rigour and clear communication over speed for its own sake.
Benefits
- Salary between £120,000 and £160,000 depending on experience
- Meaningful equity
- High ownership role with direct influence on product and technical direction
This role will not suit engineers who want to build flashy demos or constantly switch problems. It will suit someone who enjoys hard systems, deep thinking, and building things that actually hold up in the real world. If you’re looking for a role where you can make meaningful decisions, work on incredibly interesting and complex problems, and be part of an exceptional team, get in touch.
Principal Software Engineer in City of London employer: SR2 | Socially Responsible Recruitment | Certified B Corporation
Contact Detail:
SR2 | Socially Responsible Recruitment | Certified B Corporation Recruiting Team
StudySmarter Expert Advice 🤫
We think this is how you could land Principal Software Engineer in City of 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 help you land that Principal Software Engineer role.
✨Tip Number 2
Show off your skills! Create a portfolio or GitHub repository showcasing your backend projects, especially those using Python and FastAPI. This gives potential employers a taste of what you can do and how you think about building robust systems.
✨Tip Number 3
Prepare for the interview by diving deep into system design principles. Brush up on your SQL skills and be ready to discuss how you’ve tackled complex backend challenges in the past. We want you to shine and show them you’re the right fit!
✨Tip Number 4
Don’t forget to apply through our website! It’s the best way to ensure your application gets seen. Plus, we love seeing candidates who are proactive and take the initiative to connect with us directly.
We think you need these skills to ace Principal Software Engineer in City of London
Some tips for your application 🫡
Tailor Your CV: Make sure your CV reflects the skills and experiences that align with the job description. Highlight your backend engineering experience, especially with Python and systems design, to show us you’re the right fit.
Craft a Compelling Cover Letter: Use your cover letter to tell us why you care about building robust systems over chasing trends. Share specific examples of your past work that demonstrate your problem-solving skills and technical expertise.
Showcase Your Projects: If you've worked on complex backend systems or data ingestion pipelines, don’t hold back! Include links to your projects or GitHub repositories to give us a taste of your coding style and capabilities.
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 this exciting opportunity!
How to prepare for a job interview at SR2 | Socially Responsible Recruitment | Certified B Corporation
✨Know Your Tech Stack Inside Out
Make sure you’re well-versed in Python, FastAPI, and SQL. Brush up on your knowledge of building complex backend systems and data models. Be ready to discuss how you've applied these technologies in real-world scenarios.
✨Showcase Your Problem-Solving Skills
Prepare examples of how you've tackled ambiguous challenges in previous roles. Highlight your experience in designing robust systems and how you’ve contributed to architectural decisions. This will demonstrate your ability to think critically and own problems end to end.
✨Understand the Company’s Mission
Familiarise yourself with the company’s focus on AI-powered automation and their approach to building reliable systems. Be prepared to discuss how your values align with theirs, especially regarding quality and long-term system design.
✨Communicate Clearly and Effectively
Practice articulating your thoughts clearly, especially when discussing technical concepts. Since the culture values clear communication, being able to explain your ideas succinctly will set you apart from other candidates.
