Senior Backend Developer [Payments]

We're looking for a Senior Backend Developer to lead the design and development of our payment and wallet services.

You'll build and maintain systems that serve millions of users in real-time, directly impacting our users worldwide.

This is a London-based position.

Responsibilities

• Architect and scale our core payment processing and digital wallet infrastructure.
• Lead end-to-end design of high-availability systems handling millions of transactions.
• Establish and enforce engineering best practices across the payments domain.
• Drive system reliability through comprehensive testing, monitoring, and incident response.
• Mentor engineers and contribute to technical roadmap decisions.
• Collaborate with product, compliance, and finance teams to deliver secure payment features.

Required Qualifications

• 5+ years of building backend systems in Golang [preferred] or Java.
• Proven experience with large-scale payment systems [e.g, processing, routing, fraud checks].
• Strong expertise in PostgreSQL, Redis, and designing RESTful APIs.
• Deep understanding of distributed systems, microservices, DDD, and async workflows.
• Hands-on experience with Docker, cloud platforms and observability tools.
• Knowledge of OOP, SOLID, and design patterns.

Nice to Have

• Familiarity with modern frontend frameworks [React].
• Payment compliance [PCI DSS, PSD2] standards.
• Idempotency patterns and financial system best practices.