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For Companies At a Glance
- Tasks: Design and build scalable backend services for a cutting-edge AI platform.
- Company: Fast-scaling Series A AI fintech backed by top global VCs.
- Benefits: Competitive salary, significant equity, and direct access to founders.
- Other info: Dynamic, high-growth environment with genuine ownership and accelerated learning.
- Why this job: Make a real impact in the finance sector with innovative technology.
- Qualifications: 5+ years backend experience, strong Python and PostgreSQL skills.
The predicted salary is between 100000 - 200000 £ per year.
Omnis Partners is working with a fast-scaling Series A AI fintech building next-generation workflow infrastructure for global financial institutions. This is a rare opportunity to join early in the scaling phase and help architect the backend systems powering a production-grade AI platform already deployed with major enterprise clients.
The Opportunity
As a Senior Backend Engineer, you will play a central role in designing and scaling the core backend architecture behind a high-performance AI platform operating in complex, regulated financial environments. You’ll collaborate closely with ML engineers, product teams, and infrastructure specialists to build systems that are resilient, secure, and capable of operating at enterprise scale. This is a hands-on engineering role with real ownership; your decisions will directly influence system capability, scalability, and product direction.
What you’ll be doing
- Design and build scalable backend services and APIs powering a production AI platform.
- Develop and enhance high-volume data pipelines handling large-scale financial datasets.
- Work with ML engineers to bring machine learning models into production systems.
- Design, optimise, and scale PostgreSQL databases (schema design, indexing, performance tuning).
- Build secure systems aligned with regulatory standards including SOC 2, GDPR, and FCA expectations.
- Contribute to event-driven and distributed system architecture using async processing patterns.
- Improve system reliability, observability, and performance in live production environments.
- Participate in architecture decisions and provide mentorship to other engineers.
What they’re looking for
- 5+ years backend engineering experience building production systems at scale.
- Strong Python experience (FastAPI, Django, or Flask).
- Deep PostgreSQL expertise, including query optimisation and schema design for scale.
- Strong understanding of distributed systems, microservices, and event-driven architecture.
- Hands-on experience with Redis, caching strategies, and async processing (e.g. Celery).
- Cloud experience (Azure preferred; AWS or GCP also acceptable).
- Experience with Docker, Kubernetes, and modern CI/CD pipelines.
- Strong knowledge of security, authentication, and data protection in production systems.
- Ability to thrive in fast-moving, high-ownership engineering environments.
Why this role
- Significant ownership over backend systems and architectural direction.
- Opportunity to build AI infrastructure used in real-world enterprise finance use cases.
- Direct access to founders with multiple successful venture-backed exits.
- High-growth environment where engineering impact is immediate and visible.
- Chance to help define a category-leading AI platform at Series A stage.
The reality
This is not a slow-moving environment. Priorities shift, complexity is high, and expectations are ambitious. You’ll need to be comfortable working with autonomy, ambiguity, and rapid iteration. In return, you’ll get genuine ownership, accelerated learning, and the opportunity to shape a company at a pivotal stage of growth.
Senior BackEnd Engineer in City of London employer: Omnis Partners
Contact Detail:
Omnis Partners Recruiting Team
StudySmarter Expert Advice 🤫
We think this is how you could land Senior BackEnd Engineer in City of London
✨Network Like a Pro
Get out there and connect with people in the industry! Attend meetups, webinars, or even just grab a coffee with someone who works at a company you're interested in. Building relationships can open doors that a CV just can't.
✨Show Off Your Skills
Don’t just talk about your experience; show it! Create a portfolio or GitHub repository showcasing your projects, especially those related to backend systems and AI. This gives potential employers a real taste of what you can do.
✨Ace the Interview
Prepare for technical interviews by practicing coding challenges and system design questions. Be ready to discuss your past projects in detail, especially how you've tackled complex problems in high-pressure environments.
✨Apply Through Our Website
When you find a role that excites you, apply through our website! It’s the best way to ensure your application gets seen by the right people. Plus, we love seeing candidates who are proactive about their job search.
We think you need these skills to ace Senior BackEnd Engineer in City of London
Some tips for your application 🫡
Tailor Your CV: Make sure your CV reflects the skills and experiences that match the Senior Backend Engineer role. Highlight your backend engineering experience, especially with Python and PostgreSQL, to show us you’re the right fit!
Craft a Compelling Cover Letter: Use your cover letter to tell us why you’re excited about this opportunity. Share specific examples of how you've designed scalable systems or worked in fast-paced environments, so we can see your passion and expertise.
Showcase Your Projects: If you’ve worked on relevant projects, don’t hesitate to include them! Whether it’s a personal project or something from your previous job, we want to see how you’ve applied your skills in real-world scenarios.
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 don’t miss out on any important updates during the process!
How to prepare for a job interview at Omnis Partners
✨Know Your Tech Stack Inside Out
Make sure you’re well-versed in the technologies mentioned in the job description, especially Python frameworks like FastAPI, Django, or Flask. Brush up on your PostgreSQL skills, focusing on query optimisation and schema design, as these will likely come up during technical discussions.
✨Showcase Your Problem-Solving Skills
Prepare to discuss specific challenges you've faced in previous roles, particularly around building scalable backend systems or optimising data pipelines. Use the STAR method (Situation, Task, Action, Result) to structure your answers and highlight your impact.
✨Understand the Business Context
Familiarise yourself with the fintech landscape and the specific challenges faced by AI platforms in regulated environments. This will help you demonstrate how your technical skills can directly contribute to the company’s goals and the needs of their enterprise clients.
✨Be Ready for a Hands-On Technical Assessment
Expect a practical coding challenge or system design exercise during the interview. Practice coding problems related to backend services and APIs, and be prepared to discuss your thought process and design decisions clearly and confidently.