Notes on backend engineering, data engineering, system design, and building production systems.
Java's WatchService makes directory watching straightforward — but spin up a thread pool and you've got a race condition waiting to corrupt your data. Here's how I used the Observer pattern and per-path ReentrantLocks to fix it.
How I built Data Preprocessor — a published JetBrains Marketplace plugin that brings CSV, Excel, and JSON profiling, cleaning, and pandas code generation directly into IntelliJ IDEA — and what I learned shipping a real IDE plugin from scratch.
How I engineered a system that processes ~2TB/hr of RTSP video streams across 11 concurrent venues — the architecture decisions, the bottlenecks, and what I'd do differently.
The before-and-after of replacing a manual, error-prone deployment process with a fully automated pipeline — what broke, what worked, and the exact setup I now use.
The specific techniques — from N+1 query elimination to index-aware JPQL — that produced a 30% database performance improvement in a production Spring Boot application.