Senior Software Engineer (AI x Financial Modelling) - Rust/TypeScript

Do you have a track record of building exceptional software and want to work on a genuinely ambitious AI product?

Are you excited by high ownership, cutting-edge AI tooling, deep technical challenges, and the opportunity to become a technical leader within a small, elite engineering team?

🚀 Software Engineer – AI x Financial Modelling 🚀

💰 Salary: Up to £250k DOE + equity

📍 Location: London - onsite 5 days per week

🌍 Will relocate and sponsor

🧠 Experience: Exceptional engineers – high agency and strong technical fundamentals

I’m excited to be working with a very ambitious AI startup reinventing how businesses make some of their biggest decisions. They’re starting by building the best AI add-in for complex financial modelling in Excel – essentially Cursor for financial modelling.

Financial models sit underneath huge decisions across M&A, private equity, investment, corporate strategy and consulting, yet the tooling behind them remains incredibly manual and outdated.

They’re building something fundamentally different.

Long-term, their ambition is to create an AI operating system for the entire strategic decision lifecycle – spanning Excel, PowerPoint, email and meetings. They’re tackling a potentially enormous new category at the intersection of AI, software engineering and financial decision-making.

They’re now looking for exceptional Software Engineers to join a small, extremely high-calibre engineering team and help build the product from the ground up.

💡 You’ll work directly on:

• Owning features end-to-end – from Rust services and backend infrastructure through to the frontend
• Using the latest AI tools and models to ship high-quality software at exceptional speed
• Building and improving AI agents, including their harness, tools and context optimisation
• Writing highly performant software – removing allocations, optimising queries and caching aggressively
• Owning and improving backend infrastructure and CI pipelines
• Debugging low-level issues and continuously optimising system performance
• Working closely with design to ensure every feature feels polished, beautiful and consistent
• Taking increasing technical ownership as the company and product scale

✅ They’re particularly interested in engineers who have:

• Evidence of being a top-centile engineer
• Exceptional problem-solving ability and strong software engineering fundamentals
• High agency, determination and a genuine desire to take ownership
• The ability to move quickly, learn new technologies and wear multiple hats
• A strong interest in AI and experience using modern AI coding tools effectively
• The ability to work across the stack rather than being restricted to one area
• A genuine passion for building great products, not simply writing code

💻 Tech stack:

• Rust (but they are open to any low-level language e.g. C++)
• TypeScript
• React
• AI / LLM tooling
• Backend infrastructure & DevOps

🎯 Bonus points for:

• Competitive programming experience e.g. Olympiads or Programming Contests
• Trading or financial technology background
• AI Tech experience
• Experience building AI agents

🔎 What they’re looking for:

• High agency – you see a problem and take ownership of solving it

Interested in relocating to United Kingdom? Check out our comprehensive Relocation Jobs in United Kingdom page with detailed relocation packages and benefits.

• Technical excellence – you care about performance, architecture and writing exceptional software
• AI-native mindset – you understand that AI is now an essential part of the engineering workflow
• Speed + quality – you can leverage AI to move incredibly quickly without becoming a “vibe coder”
• Curiosity – you enjoy getting into unfamiliar areas and figuring things out
• Product mindset – you care about how the software feels, not just whether it works
• Leadership potential – over time, you’ll have the opportunity to own significant parts of the product

🚀 Why join?

• Join a small, exceptionally strong engineering team with backgrounds including Cambridge and UCL, Jane Street and Bloomberg
• Work on a genuinely ambitious AI product tackling a huge, under-served problem
• Own features across the entire stack rather than being confined to one area
• Work at the cutting edge of AI-native software development
• Have significant influence over the technical direction and product
• Opportunity to become a technical leader and own major parts of the product as the company scales
• Build something from the ground up in a highly ambitious environment
• Work closely with an exceptional designer and engineering team to create a product that is both technically excellent and beautiful

If you’re an exceptional engineer who wants to work at the intersection of AI, financial modelling and high-performance software, with the opportunity to have genuine ownership and impact from day one, this is a seriously exciting opportunity.

Interested? Apply now 🚀