Kotlin Developer

Senior Backend Software Engineer

📍 London (Hybrid)

💰 Salary up to £130,000 + Equity

We’re working with a fast-growing fintech startup building modern infrastructure for finance teams. Their platform helps high-growth companies automate and manage complex revenue workflows replacing manual processes and outdated systems with scalable, reliable software.

Following strong product adoption and a recent funding round, they’re now looking for a Senior Backend Engineer to help design and scale the core systems that process critical billing and usage data.

The Role

You’ll be working on backend infrastructure responsible for ingesting and processing high-volume usage events that directly power billing, invoicing, and financial reporting.

This is a highly impactful role where reliability and accuracy are essential, the systems you build will handle revenue-critical data for rapidly growing businesses.

You’ll join a small, collaborative engineering team with real ownership over architecture and platform direction.

What You’ll Be Doing

• Designing and building backend services that process large volumes of event data
• Developing scalable ingestion and streaming pipelines
• Architecting systems that balance performance, reliability, and cost at scale
• Improving data models and query performance for analytics and reporting workloads
• Contributing to core platform architecture and infrastructure decisions
• Working closely with product and engineering teams to deliver new capabilities

What They’re Looking For

• Strong backend engineering experience building scalable systems
• Experience with event-driven architectures or streaming data pipelines
• Solid understanding of distributed systems and infrastructure design
• Experience working with strongly typed backend languages (e.g. Kotlin, Java, Go, Rust, etc.)
• Comfort working with cloud infrastructure and modern DevOps practices
• Ability to operate in a fast-moving startup environment

Why This Role?

• Early opportunity to shape the architecture of a rapidly growing platform
• Work on systems where reliability and accuracy truly matter
• Small, highly capable engineering team
• Strong growth trajectory and well-funded environment
• Competitive salary £115K–£130K + meaningful equity