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- Tasks: Architect and build innovative financial infrastructure with cutting-edge technology.
- Company: Join a pre-seed fintech revolutionising cross-border commerce.
- Benefits: Significant equity, high ownership role, and the chance to shape engineering culture.
- Other info: Work in a dynamic environment with 25+ design partners and industry veterans.
- Why this job: Be a founding technical leader and make a real impact in the fintech space.
- Qualifications: 5+ years of full-stack experience with React/TypeScript and Node.js or Python.
The predicted salary is between 80000 - 100000 £ per year.
Pre-seed fintech building the financial operating system for the stablecoin era.
Join a high-growth fintech as the founding technical leader building the future of cross-border commerce. You will own the technical architecture for a platform integrating Stellar/USDC rails with an AI-powered Agentic CFO layer. This is a high-ownership role driving product execution from early design partners to global scale.
Location: London, UK
Why this role is remarkable:
- Significant founding-level equity (1–5%) and the chance to shape the engineering culture from the ground up as the most important hire of 2026.
- Lead a product with 25+ signed design partners, founded by an industry veteran who previously scaled a major European crypto card issuer.
- Build at the cutting edge of finance, combining programmable stablecoin infrastructure with autonomous AI agents to automate treasury and cross-border payments.
What You Will Do:
- Architect and build core treasury infrastructure including multi-currency wallets, stablecoin on/off ramps, and yield optimization protocols.
- Develop the Agentic CFO layer featuring LLM-powered financial intelligence, autonomous action pipelines, and semantic caching.
- Lead the end-to-end execution of a merchant dashboard using React/TypeScript and Node.js/Python to simplify complex global financial operations.
The ideal candidate:
- 5+ years of full-stack experience with production ownership of React/TypeScript and Node.js or Python backend systems.
- Proven track record shipping AI/LLM-powered products including agentic workflows, RAG pipelines, or LLM infrastructure.
- Previous experience as an early engineer or CTO at a startup with a strong bias for shipping in fast-paced, high-ownership environments.
Senior Full-Stack Engineer at Pre-seed fintech building stablecoin infrastructure in London employer: Jack & Jill
Contact Detail:
Jack & Jill Recruiting Team
StudySmarter Expert Advice 🤫
We think this is how you could land Senior Full-Stack Engineer at Pre-seed fintech building stablecoin infrastructure in London
✨Tip Number 1
Network like a pro! Reach out to folks in the fintech space, especially those who are already working at companies you’re interested in. A friendly chat can open doors and give you insider info that could help you stand out.
✨Tip Number 2
Show off your skills! Create a portfolio or GitHub repo showcasing your projects, especially those involving React, Node.js, or AI. This is your chance to demonstrate your expertise and passion for building innovative solutions.
✨Tip Number 3
Prepare for interviews by brushing up on your technical knowledge and soft skills. Practice coding challenges and be ready to discuss your past experiences in detail. Remember, they want to see how you think and solve problems!
✨Tip Number 4
Don’t forget to apply through our website! We love seeing candidates who take the initiative. Plus, it’s a great way to ensure your application gets into the right hands quickly.
We think you need these skills to ace Senior Full-Stack Engineer at Pre-seed fintech building stablecoin infrastructure in London
Some tips for your application 🫡
Show Your Passion for Fintech: When writing your application, let your enthusiasm for fintech shine through! We want to see how excited you are about building the future of cross-border commerce and stablecoin infrastructure. Share any relevant projects or experiences that highlight your passion.
Tailor Your Experience: Make sure to customise your application to reflect the skills and experiences that align with our job description. Highlight your full-stack experience, especially with React/TypeScript and Node.js or Python. We love seeing how your background fits into our vision!
Be Clear and Concise: Keep your application straightforward and to the point. We appreciate clarity, so avoid jargon and focus on what makes you a great fit for this role. A well-structured application helps us understand your qualifications quickly!
Apply Through Our Website: Don’t forget to submit your application through our website! It’s the best way for us to receive your details and ensures you’re considered for the role. Plus, it shows you’re serious about joining our team at StudySmarter!
How to prepare for a job interview at Jack & Jill
✨Know Your Tech Stack Inside Out
Make sure you’re well-versed in React, TypeScript, Node.js, and Python. Brush up on your knowledge of multi-currency wallets and stablecoin infrastructure, as these are key components of the role. Be ready to discuss your past projects and how you’ve used these technologies to solve real-world problems.
✨Showcase Your Leadership Skills
Since this is a founding technical leader position, it’s crucial to demonstrate your leadership experience. Prepare examples of how you've led teams or projects in fast-paced environments. Highlight your ability to drive product execution and shape engineering culture, as this will resonate with the company’s vision.
✨Prepare for Technical Challenges
Expect to face technical challenges during the interview. Practice coding problems related to full-stack development and be ready to explain your thought process. You might also be asked about AI/LLM-powered products, so brush up on those concepts and be prepared to discuss how you would implement them in this role.
✨Understand the Fintech Landscape
Familiarise yourself with the current trends in fintech, especially around stablecoins and cross-border commerce. Being able to discuss the implications of these technologies and how they can be integrated into the company's vision will show your genuine interest and understanding of the industry.