Yongjun Hong is a backend engineer at NAVER WEBTOON and an open-source contributor to JUnit5, spring-projects, naver/fixture-monkey, and more. He is currently a committer for apache/seata and has been selected as a GSoC'25 contributor for a Kotlin & Gradle project. He enjoys collaborating on projects, sharing knowledge, and continuously learning new technologies to improve his skills.

Recently, he has been particularly interested in test code. To him, test code is not just for validation. It helps other developers understand how to use his code and serves as a foundation for efficient refactoring, making it essential for maintaining high-quality software.

He is also interested in distributed transactions, especially their implementation and challenges within microservices architectures. It's a complex but fascinating area, and he has been sharing his thoughts through recent blog posts.

• JUnit Framework
  • Introduce feature flag for auto-closing AutoCloseable in Jupiter's ExtensionContext.Store #4452
  • Provide mechanism for managing resources across engines and executions #4281
  • Implement Parallel Method Execution in JUnit-Vintage engine #4242
  • Support parallelization in Junit-Vintage-engine #4135
  • Implement include and exclude filtering when calling registerAutoDetectedExtensions #4120
  • Add include matching on ClassNamePatternFilterUtils #4115
• spring-boot
  • Add Fail fast mechanism when both management base path and endpoint mapping are set to / #45251
  • Ensure DefaultErrorAttributes adds JSON serialization safe errors #43330
• spring-framework
  • Fall back to JDK Dynamic proxy if CGLIB proxy creation fails #35344
  • Reject effectively private handler methods on CGLIB proxied controllers #35352
• apache-seata
  • Add ChannelEventListener support to prevent memory leaks #7337
  • Enforce account initialization and disable default credentials #7261
  • Use shared EventLoop for TM and RM clients to reduce thread overhead and improve performance #7179
  • Implement scheduled handling for end status transaction #7133
• naver/fixture-monkey
  • Implement Random Selection of Register Operations When Not Using selectName #1108
  • Implement a Matcher interface to manage ArbitraryBuilders with a single variable #1062
  • Add register and select ArbitraryBuilder by name #1036
• LG/fosslight
  • Refactor existing tox test to pytest #225
  • Change SCANOSS Invocation Method from Command Line to Library Function #178

• Centralized POM Configuration Management with kotlin-pom-gradle
• Spring 관점에서 보는 Seata의 내부 통신
• Apache Seata란?
• 내가 JUnit5에 글로벌 Extension 필터링 기능을 추가한 이야기
• 내가 JUnit5에 병렬화를 도입한 이야기 - 메서드 단위
• 내가 JUnit5에 병렬화를 도입한 이야기 - 클래스 단위

• 내 블로그가 코틀린 공식 블로그에?
• Spring Framework에 기여한 이야기

• yongjunh@apache.org
• Let's have a virtual coffee ☕