System Performance Engineer

At Flarion, we’re building a new kind of big data accelerator targeting technologies like Apache Spark, Ray, and Hadoop. We combine low-level native implementations in Rust and C++ (leveraging Arrow, Polars, DataFusion) with intelligent query optimization that makes workloads run dramatically faster and cheaper.

We’re looking for a Principal Engineer to focus on performance optimizations for our in house distributed data systems. It’s a hands-on position where you’ll profile, debug, and tune complex systems for speed and efficiency.

What You’ll Do

• Profile and optimize distributed systems at scale (Spark, Ray, Hadoop, or similar).
• Dig into complex, multi-layer codebases and improve their runtime performance.
• Work with Arrow/Polars/DataFusion internals to shape efficient execution paths.
• Translate insights from profiling and benchmarks into production-ready improvements.
• Own projects end-to-end: identify bottlenecks, design solutions, test, and ship them.

Must-haves

• Proven track record of performance optimization in distributed systems or large-scale data platforms.
• Hands-on coding experience with performance-critical systems in Languages such as Scala, Python, Rust, or C++.
• Experience profiling, debugging, and tuning complex distributed codebases.
• Ownership mindset: ability to take projects from problem definition to production.
• Strong problem-solving skills and attention to detail.

Preferred

• MSc or PhD in Computer Science, Electrical Engineering, or related fields.
• Experience with Spark internals, Ray, Hadoop, or similar distributed compute frameworks.
• OSS contributions to distributed systems, query engines, or performance-critical libraries (e.g., Spark, Presto/Trino, Arrow, DataFusion, Polars).
• Familiarity with database internals, compilers, or query optimization is a plus, but not a core requirement.
• Experience building or tuning high-performance systems in production.

Experience

• 7+ years working in distributed systems, databases, or high-performance infrastructure.
• Hands-on experience reducing latency, improving throughput, or lowering resource consumption in real-world systems.
• Demonstrated ability to improve performance in multi-tenant, production-grade environments.

Values We Screen For

Excellence. Ownership. Collaboration. Self-Starter. Integrated Thinking. Ambition. Innovation.

Why Join

This role puts you at the heart of what makes Flarion different: making large-scale distributed systems run faster, leaner, and more reliable. You’ll work with low-level engines, contribute to open-source, and deliver optimizations that have immediate impact on some of the largest data workloads in the world.