During January 2025, Koji focused on enhancing the VKCOM/kphp repository by developing the HTTP Headers Sent State API, which enables the runtime to determine if HTTP headers have already been sent during response handling. This feature was implemented in C++ and PHP, with supporting Python tests to validate headers_sent behavior after flush operations and within shutdown callbacks. Koji’s work improved the correctness and observability of the HTTP response lifecycle, addressing edge cases that could lead to header-related regressions. The technical approach emphasized runtime development, system programming, and robust testing, contributing to greater reliability in web response handling for kphp applications.