21 hours ago
London, United KingdomMid Level
Responsibilities
- Design, profile, and implement core database features involving storage formats, index structures, and recovery paths.
- Diagnose concurrency bugs, race conditions, and lock contention.
- Improve latency through CPU, memory, off-heap memory, and disk I/O performance engineering.
- Review designs and pull requests with emphasis on correctness, data integrity, and maintainability.
- Contribute to technical direction and architectural trade-offs as the database engine evolves.
- Write thorough tests and collaborate through data-driven design and code review.
Requirements
- Systems programming experience and comfort working close to the hardware.
- Experience with Java or transferable systems programming experience in C++, Rust, or Go, including understanding of memory layouts and concurrency.
- Strong understanding of threads, locks, atomic operations, cache locality, and algorithmic complexity.
- Ability to write thorough tests and participate constructively in technical discussions and code reviews.
- Prior experience with database internals, storage engines, or file systems is a bonus.
- Deep JVM knowledge, including garbage collection behavior, JIT compilation, and off-heap memory, is a bonus.
- Hands-on experience with async-profiler, JFR, or perf is a bonus.
- Experience navigating and evolving large, mature codebases is a bonus.
Benefits
- Regular “Do What You Want” weeks provide dedicated time for personal prototypes or tooling improvements.
- The team operates across Malmö and London.
- Neo4j describes its workplace as collaborative, inclusive, diverse, and equitable.
About Neo4j
Neo4j builds a native graph database and graph analytics platform for developers and data teams, available as self-managed software and the Aura managed cloud. It powers knowledge graphs, recommendations, fraud detection, and other relationship-centric applications via the Cypher query language and integrations across data tools. Founded in 2007 and headquartered in San Mateo, the privately held company commercializes the open-source Neo4j project with enterprise subscriptions and support.