Find a job 
Featured Companies 
Featured Universities 
For Companies At a Glance
- Tasks: Join us to design, build, and launch a cutting-edge fintech platform.
- Company: We're an innovative fintech startup revolutionising global payments with a fresh approach.
- Benefits: Enjoy competitive salary, equity options, and flexible remote work opportunities.
- Why this job: Be a founding engineer shaping the future of finance in a dynamic, mission-driven environment.
- Qualifications: 3+ years in backend systems with C#/.NET; experience in DDD, CQRS, and microservices required.
- Other info: Work in-person in London, with some flexibility for remote Fridays.
The predicted salary is between 43200 - 72000 £ per year.
We are an early-stage fintech startup re-wiring the global payments infrastructure. Today, sending money across borders is slow, expensive, and fragmented. We are here to fix that—making instant cross-border payments a reality. We are building from zero—no tech debt, no legacy systems. Just a clean slate, strong vision, and higher standards. Now we are looking for a founding backend engineer to join us at the ground level and help bring this platform to life.
The Role
- You will work directly with the founders to design, build, and launch our core platform.
- This is a hands-on, high-impact role: you will write code daily, influence key architectural decisions, and ship fast using modern tools and AI.
- Build a modern backend from scratch in C#/.NET 8 with a clean, event-driven architecture.
- Help architect a scalable system using CQRS, Event Sourcing, DDD, microservices.
- Own key components in AWS: Lambda, SQS, SNS, DynamoDB, PostgreSQL, API Gateway.
- Work in a test-first, high-trust environment with real autonomy.
About You
- You work incredibly hard, really care about your work and take pride in what you do.
- You ship clean code, scalable systems, and solve complex problems elegantly. You are excited by ownership and unafraid of ambiguity. You move fast, but with precision.
- You use AI tools to design, code, debug, and ship faster, not just as a nice-to-have but a MUST-have force multiplier.
What we are after:
- 3+ years experience building backend systems and APIs in C#/.NET.
- Strong grasp of architecture patterns: DDD, CQRS, microservices.
- Experience writing clean, testable code with a TDD mindset.
- Experience working in small teams or startups, where autonomy and speed matter.
- Comfort with cloud-native infrastructure (preferably AWS).
Nice to Have:
- Hands-on experience with event sourcing in production.
- Background in payments, fintech, or secure data platforms.
- Experience building B2B platforms or financial APIs.
Why Join Us?
- Build from 0 to 1: You will shape the architecture, team, and product from day one.
- Real ownership: You won’t be a cog—you will be a core part of the company’s foundation.
- Mission-driven: Help reinvent a critical piece of global financial infrastructure.
- Equity upside: Generous options in what we believe can be a generational fintech company.
- Work with intensity and purpose, in-person with a small team of true builders in London.
Why you shouldn’t join
- Expectations are incredibly high.
- You are looking for a comfy job with a 40 hour a week commitment with predictable hours and minimal pressure.
- You don’t see the value in using AI to enhance engineering teams.
Logistics
- Location: In-person in London 5 days a week with some flexibility (e.g. remote Fridays).
- Compensation: Competitive salary + high-equity package.
To apply please send your CV and a quick note on why you want to join to hello at 3degrees dot co. No visa sponsorship of any kind at this point.
Contact Detail:
Stealth Startup Recruiting Team
StudySmarter Expert Advice 🤫
We think this is how you could land Founding Backend Engineer
✨Tip Number 1
Familiarise yourself with the latest trends in fintech and global payments. Understanding the current challenges and innovations in this space will help you engage in meaningful conversations during interviews and demonstrate your passion for the industry.
✨Tip Number 2
Showcase your experience with C#/.NET and cloud-native infrastructure, particularly AWS. Be prepared to discuss specific projects where you've implemented these technologies, as this will highlight your hands-on skills and readiness for the role.
✨Tip Number 3
Emphasise your ability to work in a fast-paced, startup environment. Share examples of how you've thrived in small teams, taken ownership of projects, and navigated ambiguity, as these qualities are crucial for a founding engineer.
✨Tip Number 4
Prepare to discuss how you've used AI tools in your development process. Since the role requires leveraging AI for efficiency, being able to articulate your experience with these tools will set you apart from other candidates.
We think you need these skills to ace Founding Backend Engineer
Some tips for your application 🫡
Understand the Company: Before applying, take some time to understand the fintech startup's mission and vision. Familiarise yourself with their approach to re-wiring global payments and how your skills as a backend engineer can contribute to this goal.
Tailor Your CV: Make sure your CV highlights your experience with C#/.NET, architecture patterns like DDD and CQRS, and any relevant work in cloud-native infrastructure, particularly AWS. Emphasise your ability to write clean, testable code and your experience in fast-paced environments.
Craft a Compelling Note: In your application note, express your enthusiasm for the role and the company. Highlight why you are excited about the opportunity to build from scratch and how your background aligns with their needs. Be specific about your experience and how it relates to the job description.
Showcase Your Problem-Solving Skills: In your application, consider including examples of complex problems you've solved in previous roles. This could be through projects where you implemented scalable systems or used AI tools effectively. Demonstrating your problem-solving abilities will resonate well with the company's expectations.
How to prepare for a job interview at Stealth Startup
✨Showcase Your Technical Skills
Be prepared to discuss your experience with C#/.NET and the architectural patterns mentioned in the job description. Bring examples of past projects where you've implemented DDD, CQRS, or microservices, and be ready to explain your thought process.
✨Demonstrate Problem-Solving Abilities
Expect to face technical challenges during the interview. Practice articulating how you approach complex problems and the strategies you use to find elegant solutions. Highlight your experience with test-driven development and clean code practices.
✨Emphasise Your Autonomy and Ownership
This role requires a high level of independence. Share experiences from previous roles where you took ownership of projects or worked in small teams. Illustrate how you thrive in fast-paced environments and can make impactful decisions.
✨Align with Their Mission
Research the company’s vision for transforming global payments. Be ready to express why you are passionate about fintech and how your values align with their mission. This will show that you are not just looking for a job, but are genuinely interested in contributing to their goals.
