Senior Backend Engineer — Low-Latency AI Search

Nebius Group; Greater London; On-site; GBP 90,000 - 140,000; Full time

Benefits offered by this job

Competitive compensation

Career growth and learning

Flexibility and ownership

Collaborative culture

Impactful AI projects

International environment

Job summary

Nebius is seeking a Senior Software Engineer in the United Kingdom to join the runtime systems of a novel search engine crafted for agentic AI consumption. You will build low-latency, high-throughput services that handle real-time search queries on the critical path, shaping performance and efficiency across the stack.

You will collaborate with indexing and ML teams to integrate retrieval and ranking components, optimize CPU/memory usage, and ensure observability and reliability in production

Qualifications

• 5+ years of experience as a software engineer working on production backend systems
• Strong hands-on expertise in C++ or Rust in real-world, high-load services
• Experience building and operating high-load, low-latency user-facing systems handling thousands of RPS under strict latency constraints
• Understanding of CPU, memory, networking, and data access from a systems perspective

Responsibilities

• Design, implement, and operate core runtime services for serving search queries at scale
• Build and optimise request flows, including query processing, retrieval orchestration, and response assembly under strict latency budgets
• Develop systems that maintain performance and predictability under high load
• Optimise CPU, memory, and data access patterns in performance-critical paths
• Ensure reliability, observability, and predictability across production services
• Collaborate with indexing and ML teams to integrate retrieval and ranking components
• Support experimentation and iteration through controlled rollouts and benchmarking

Skills

C++

Rust

High-load systems

Performance optimization

Observability

Cross-functional collaboration

Job description

Nebius is seeking a Senior Software Engineer in the United Kingdom to join the runtime systems of a novel search engine crafted for agentic AI consumption. You will build low-latency, high-throughput services that handle real-time search queries on the critical path, shaping performance and efficiency across the stack.

You will collaborate with indexing and ML teams to integrate retrieval and ranking components, optimize CPU/memory usage, and ensure observability and reliability in production