Senior Search Core Engineer: High-Scale, Low-Level Systems

Perplexity; Greater London; On-site; GBP 90,000 - 130,000; Full time

Job summary

Perplexity is seeking a Senior/Expert Systems Engineer to help shape the next generation of search technologies and architectural decisions. Join our Search Core team to influence design, implementation, and performance across critical components.

You will design core search engine components, build scalable data processing, and push hardware performance through low-level optimizations while tackling multithreading and system-level challenges for production-grade reliability.

Qualifications

• 3+ years of hands-on systems programming experience (Rust, C++, C, or similar).
• Owns full project lifecycle — you don't just write a fast inner loop, you care about how the system is built, deployed, operated, and scaled in production.
• Knowledge of Python or another scripting language.
• Passion for writing clean, efficient, and scalable systems-level code.
• Strong knowledge of algorithms and data structures, and the ability to apply them effectively.
• Deep understanding of multithreading, including various approaches, challenges, and trade-offs.
• Experience building high-load, distributed, and hardware-adjacent services.
• Solid understanding of Linux internals (syscalls, networking stack, memory model, kernel tuning).
• Familiarity with low-level optimization techniques (memory management, cache efficiency, SIMD, profiling).

Responsibilities

• Design and build core search engine components, including indexing pipelines, retrieval algorithms, and ranking systems that operate at the scale of billions of pages.
• Develop streaming and batch data processing systems for search index construction in a high-load environment.
• Push the limits of hardware performance through low-level optimizations and systems-level tuning.
• Tackle challenges in multithreading, concurrency, and system-level optimization.

Skills

3+ years experience

Full lifecycle ownership

Python or scripting

Algorithms & DS

Multithreading

High-load distributed systems

Linux internals

Low-level optimization

Tools

Kubernetes

AWS infrastructure

Job description

Perplexity is seeking a Senior/Expert Systems Engineer to help shape the next generation of search technologies and architectural decisions. Join our Search Core team to influence design, implementation, and performance across critical components.

You will design core search engine components, build scalable data processing, and push hardware performance through low-level optimizations while tackling multithreading and system-level challenges for production-grade reliability.