Java

A record of designing and building a chat system as a personal project to gain hands-on experience with Kafka and Hexagonal Architecture.

Spring MVC assigns one thread per request. When I/O waits pile up, threads sit idle. WebFlux replaces this with an event loop-based non-blocking model. A summary of the structural differences from MVC, the Reactor pattern, and when to choose which.

Korea Railroad Industry Information Center’s public-data hackathon. A three-person team built an Android app that surfaces hidden rest spaces inside subway stations, over three weeks.