Heejong enhanced security and schema precision across the semgrep/semgrep-rules and semgrep/semgrep-interfaces repositories. In semgrep-rules, he focused on strengthening security rule validation for No-Auth-Over-HTTP by updating and expanding test coverage, ensuring alignment with recent code changes to reduce risk and improve maintainability. Heejong also standardized rule ID comments for consistency. In semgrep-interfaces, he introduced fully qualified name fields to the rule schema, enabling more precise rule identification while maintaining backward compatibility with older CLI versions. His work leveraged OCaml, Python, and YAML, demonstrating depth in security analysis, data modeling, and schema definition within a short timeframe.