In April 2025, Jeongns delivered comprehensive technical documentation for hierarchical data modeling in MySQL, focusing on the Closure Table approach. Working in the Kernel360/blog repository, Jeongns authored a detailed blog post that compared Closure Table with Adjacency List, Materialized Path, and Nested Set models, providing SQL schema definitions and practical queries for managing hierarchical data. The work demonstrated strong skills in database design, SQL, and technical writing, offering engineers clear guidance for implementing and querying hierarchical structures. The documentation’s depth and clarity enhanced the repository’s knowledge base, supporting faster adoption of advanced data modeling techniques within engineering teams.