In January 2025, Seob contributed to the http4k/http4k repository by implementing OpenAPI v3 Client Credentials OAuth security support. Using Kotlin and leveraging expertise in API development and contract testing, Seob developed a dedicated contract renderer that accurately represents client credentials flows within the OpenAPI specification. The work included expanding test coverage for OAuth 2.0 security schemes, which helps prevent regressions and improves long-term maintainability. By strengthening the contract rendering architecture, Seob enabled smoother integration for OAuth2-secured clients. The depth of the work is reflected in the focus on both specification accuracy and robust testing, enhancing the reliability of http4k.