Backend Tech Lead (Java or Kotlin)

Our client is a global leader in control systems for quantum computing, scaling from individual qubits to arrays of thousands. We're looking for a hands-on Backend Tech Lead (Java) to drive the technical direction of our core backend layer and lead the engineers building it. The systems you'll own handle bursty, high-throughput workloads: thousands of requests per second, strict latency requirements, distributed coordination, hard concurrency problems. You'll shape the architecture, review the designs, and still write the code.

What Makes This Role Different:

Our clients backend team is the orchestration layer between:

• Hardware control systems (C++)

• Client-exposed SDK (Python)

• Reporting and management system (Go)

• Business logic (Java/Kotlin + Spring) as Lead Software Engineer, you're the technical anchor of that layer.

When teams disagree on where a boundary belongs, you drive the decision. When a design has a flaw nobody's spotted, you catch it. When the hardest problem lands, you're close enough to the code to pick it up yourself.

Requirements:

• 8+ years building backend systems in Java/Kotlin, including experience leading the technical work of a team

• You still write code, and you're good at it - this is not a management-only role

• Deep concurrency expertise: race conditions, lock ordering, async patterns - and you can teach others to reason about them

• Architecture at system scale: throughput, distributed coordination, performance trade-offs

• Design review leadership: you can take apart a design constructively and propose one that will hold

• A track record of mentoring engineers who got better because of you.

Desirable Skills:

• Spring experience

• gRPC-based communication

• Python programming

• Experience in polyglot environments

• AI coding agent experience, with opinions on how a team should use them well

• Experience with real-time, low-latency, or hardware-adjacent systems

If you are an experienced Java Technical Lead looking to join a seriously fast moving company, please send a copy of your CV directly to the advertisement for immediate consideration.