MongoDB

Software Engineer 3, Query Optimization

Dublin, Ireland

Mid-Level

HYBRID

MongoDB's Server Query team is hiring a Software Engineer 3 focused on Query Optimization, based in Dublin (hybrid). You'll work on the MongoDB query engine, covering the full lifecycle of query processing from parsing and optimization to plan selection and execution. The role involves designing and implementing new features related to query performance, robustness, and language enhancements, while collaborating across a global team. Ideal candidates have 3+ years of experience in data-intensive environments, strong CS fundamentals, and an interest in database query engine theory and practice.

C++

Data structures and algorithms

Software architecture and design

Query engine development

Large codebase navigation

Code review

Distributed systems

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