During February 2026, Sander Brienen focused on backend development for the payloadcms/payload repository, addressing a critical file upload issue. He resolved a bug related to the tempFileDir configuration by implementing robust path resolution using Node.js and TypeScript, ensuring that absolute paths were handled correctly and preventing path duplication. This solution improved the reliability of file uploads and reduced related support issues by aligning the behavior of temp file handling across different environments. Sander’s work demonstrated a solid understanding of file handling and backend systems, delivering a targeted fix that enhanced the stability and maintainability of the upload process.