Kyan contributed to the withastro/astro repository by addressing a targeted reliability issue in RSS feed delivery. He implemented a fix to normalize the RSS Content-Type header to 'application/rss+xml' with UTF-8 charset, ensuring proper encoding and compatibility across various feed readers and clients. This patch, applied through a documented changeset, improved downstream support for the @astrojs/rss integration and enhanced traceability for future maintenance. Working primarily with JavaScript and TypeScript, Kyan leveraged his skills in API and backend development to validate the solution across major RSS clients, reducing parsing issues and supporting robust interoperability within the Astro ecosystem.