Principal Software Engineer - Performance Tuning - Elasticsearch

Elastic, the Search AI Company, enables everyone to find the answers they need in real time, using all their data, at scale , unleashing the potential of businesses and people.

Elasticsearch powers search, observability, and AI retrieval for the world's largest organisations. We are seeking a Principal Software Engineer to join the Elasticsearch Performance team. In this role, you will lead architectural and code-level performance engineering initiatives. Your goal is to drive the continuous optimisation and predictability of Elasticsearch performance, partnering with area-specific teams to unlock the full potential of our software.

Responsibilities

• Owning core performance engineering initiatives from architecture to production, focusing on the delivery of high-impact optimisations. Leading the technical design, plan, and execution for major architectural and code-level performance improvements.
• Developing foundational performance models and methodologies for complex, distributed systems.
• Driving optimisation strategies to ensure Elasticsearch remains performant, predictable, and scalable in diverse environments.
• Profiling and analysing system behaviour to identify bottlenecks in logging, metrics, vector search, and ES|QL.
• Ensuring robust performance benchmarks and regression detection for both stateful and stateless (Serverless) architectures.
• Collaborating across the company to embed performance-first thinking into new features from the outset.
• Drive automation efforts by designing and building AI-assisted optimisation harnesses that streamline profiling, hypothesis testing, and benchmarking.
• Mentoring and coaching other engineers, fostering a culture of technical excellence and performance-aware development.

Requirements

• You have deep knowledge of Java internals and JVM memory management. You understand how concurrency models work. You can write code that is high-performance, thread-safe, and lock-free. This experience includes working with large open-source and enterprise codebases.
• You have proven experience in profiling and optimising distributed systems. This includes deep experience with benchmarking tools (e.g., flamegraphs, JMH, Rally), identifying performance regressions, and implementing algorithmic or hardware-aware optimisations.
• You have a solid comprehension of distributed systems architecture, including partition tolerance, cluster state propagation, and scaling challenges in large-scale data stores.
• You have a proven track record of using AI or advanced tooling to accelerate optimisation, debug complex performance issues, and automate benchmarking workflows.
• You possess the ability to collaborate across functions and teams, acting as a force multiplier for performance engineering across the organisation.
• You possess the ability to collaborate across functions and teams and seamlessly transition between different projects, codebases, or teams based on business priorities.
• You can work autonomously, drive decisions and result in a distributed team by leveraging asynchronous, direct, and transparent communication.

Nice to Have

• Experience integrating high-performance native libraries (e.g., C++, Rust, SIMD-accelerated code) into Java applications.
• Deep knowledge of modern storage engine performance, index modes, or vector search optimisations.
• Experience defining and managing Performance SLAs and success criteria for distributed systems.
• Experience working on the internals of a large-scale data store or search engine.
• Experience working on the internals of a data store or search engine.

Compensation

The typical starting salary range for this role is: 369,400 zł - 584,300 zł PLN.

Benefits

• Competitive pay based on the work you do here and not your previous salary.
• Health coverage for you and your family in many locations.
• Ability to craft your calendar with flexible locations and schedules for many roles.
• Generous number of vacation days each year.
• Increase your impact - We match up to $2000 (or local currency equivalent) for financial donations and service.
• Up to 40 hours each year to use toward volunteer projects you love.
• Embracing parenthood with a minimum of 16 weeks of parental leave.