About - Heneli Kailahi

👋 I'm currently in the market for backend and full-stack software engineering positions. Please send hiring inquiries via Linkedin or email.

Author

My name is Heneli. I'm a senior software engineer specializing in high-performance data systems and functional programming. I bridge the gap between backend architecture and data engineering to build systems that are both reliable and maintainable.

At Scarf Systems, I co-led the migration from OLTP-based pre-aggregated analytics to OLAP-based real-time analytics, scaled backend services, and integrated customer-driven controls into Scarf's metadata enrichment pipeline while delivering sub-50ms event processing times. I optimized analytical queries supporting dynamic filtering to achieve sub-second dashboard performance across billions of events, applying numerous database techniques within PostgreSQL and ClickHouse.
I'm particularly passionate about database internals and using functional programming principles to solve complex engineering challenges. My work combines rigorous system design with practical performance optimization.

Blog

This blog focuses on programming and the software industry.

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