Senior Product Engineer (Backend focused) | Cards, Payments, Stablecoins, Go | High-Growth FinTech Start-up | London, Hybrid 2 days | 90-130k + Equity

Senior Product Engineer (Backend focused) | Cards, Payments, Stablecoins, Go | High-Growth FinTech Start-up | London, Hybrid 2 days | 90-130k + Equity

(Go experience not required, a nice to have)

The Company

We're partnering with a well-funded, high-growth FinTech start-up operating at the forefront of one of the most exciting transformations in financial services: stablecoins and the future of global payments.

They're building modern financial infrastructure that bridges traditional payment systems with digital assets, helping reshape how money moves around the world.

With an ambitious product roadmap, strong financial backing and an experienced leadership team, they're now investing heavily in engineering to build the next generation of financial products.

They're looking for exceptional Product Engineers who have previously built card products or payments infrastructure, ideally within high-growth start-up or scale-up environments.

The Role | Senior Product Engineer (Backend focused) | Cards, Payments, Stablecoins, Go | High-Growth FinTech Start-up | London, Hybrid 2 days | 90-130k + Equity

The engineering challenges span card payments, AI innovation, transaction processing, distributed systems and building reliable financial products that handle real money.

You'll have significant ownership, working closely with Product and Engineering to design, build and ship business-critical functionality.

This is a particularly exciting opportunity for engineers who have experienced the pace, ambiguity and ownership of early-stage companies and want to do it again in a rapidly growing industry.

What You'll Be Doing | Senior Product Engineer (Backend focused) | Cards, Payments, Stablecoins, Go | High-Growth FinTech Start-up | London, Hybrid 2 days | 90-130k + Equity

• Build and scale complex financial products across cards, payments and modern financial infrastructure.
• Develop reliable backend services and APIs using Go.
• Work on card payment functionality, transaction processing and third-party integrations.
• Solve challenging distributed systems problems involving financial correctness, reliability and scalability.
• Contribute to infrastructure connecting traditional payment systems with stablecoin technology.
• Own engineering challenges end-to-end, from architecture through to production.
• Work closely with Product and Engineering to turn ambitious ideas into working products.
• Make pragmatic technical decisions in a fast-moving start-up environment.
• Help influence engineering standards, technical direction and product development.

Go (Golang) | Distributed Systems | AWS | APIs | Event-Driven Architecture | Databases | Payments Infrastructure

Previous Go experience isn't essential. Engineers from strong Python, Java, Kotlin, C# or other backend backgrounds who are excited to work with Go will be considered.

Payments experience and strong engineering fundamentals are more important than having worked with a particular programming language.

What They're Looking For - Senior Product Engineer (Backend focused) | Cards, Payments, Stablecoins, Go | High-Growth FinTech Start-up | London, Hybrid 2 days | 90-130k + Equity

• Cards & Payments Experience: Proven experience building card products, card issuing, card processing or complex payment infrastructure.
• Start-up Experience: Ideally, previous experience working within an early-stage or high-growth start-up, where you've had significant ownership and helped build products with limited structure.
• Strong Engineering Fundamentals: Experience building reliable, scalable backend or full-stack systems.
• Product Engineering Mindset: Someone who enjoys solving customer problems, taking ownership and shipping rather than working exclusively on isolated backend tasks.
• Distributed Systems: Strong understanding of APIs, databases, event-driven architecture and cloud infrastructure.
• Go or Willingness to Learn: Previous Go experience is advantageous but not essential.
• Ownership & Autonomy: Comfortable navigating ambiguity, making technical decisions and operating without layers of management.

Nice to have

Stablecoin payments, blockchain infrastructure, crypto payments, ledgering, reconciliation, embedded finance or experience taking a FinTech product from zero to one.

We're particularly interested in engineers who have worked in smaller, high-performing teams where they've been responsible for building and scaling products, rather than maintaining a small component of a much larger system.

Interview Focus - Senior Product Engineer | Cards, Payments, Stablecoins, Go | High-Growth FinTech Start-up | London, Hybrid 2 days | 90-130k + Equity

Expect to go deep on three areas:

Payments Experience – What card or payments products have you built, and what was your personal contribution?

Start-up Ownership – Tell us about a product or system you've helped build in a fast-moving environment. How did you navigate ambiguity and make technical decisions?

Engineering Quality – How have you approached reliability, scalability and correctness when building systems handling real financial transactions?

Why Join | Senior Product Engineer | Cards, Payments, Stablecoins, Go

• Stablecoin Revolution: Work at the intersection of traditional finance and one of the fastest-evolving areas of financial technology.
• Early-Stage Impact: Join a high-growth start-up where individual engineers have genuine influence over the product and architecture.
• Meaningful Ownership: Build important financial products rather than maintaining small features within a large organisation.
• Technical Complexity: Solve challenging problems across payments, distributed systems and financial infrastructure.
• Strong Engineering Culture: Work alongside ambitious engineers who care about quality, ownership and shipping.
• Career Growth: Help shape a growing engineering organisation as the business scales.
• Competitive

Compensation

Attractive salary and equity opportunity.

If you've built card products or complex payments infrastructure, enjoy the pace of start-ups and want to work on the future of money movement, we'd love to hear from you.

Apply with your CV and we'll be in touch if there's alignment.