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Worth Reading
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Proper Connection Pool Configuration in TypeORM & NestJS
A deep dive into connection pool configuration in TypeORM and mysql2, inspired by Naver D2's Commons DBCP guide. Learn how to calculate required connections using TPS formulas, compare Before/After production code, and understand each configuration option in depth.
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When equals/hashCode Goes Wrong: A Duplicate Payment Incident Post-Mortem
A deep dive into how forgetting to override hashCode() while implementing equals() caused duplicate payments. Includes Kafka TopicPartition analysis, HashMap internals, and code review checklists.
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Debugging a Memory Leak in Browser Automation: The Perfect Storm of Three Cleanup Paths
A deep dive into debugging a memory leak in a production system managing 50 concurrent Firefox browsers. The story of how Promise.race and finally blocks created a double-cleanup bug, and the journey to fix it.
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Multi-Platform Database Design: Building Enterprise-Grade Logging Systems
From specialized table design for new platform integration to AI-driven design validation, index optimization, and partitioning strategies - A complete guide to enterprise-grade database design
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Dissecting Kotlin's toSet(): Engineering is About Explaining Choices
A deep dive into Kotlin's toSet() method from JVM memory model to production environments. Analyzing standard library design decisions, memory overhead, GC impact, and practical guidelines for high-traffic systems.