Zero-Knowledge File Sharing: Engineering a Server That Never Holds the Keys

Most file-sharing services claim encryption while retaining server-side decryption keys; this article details a practical architecture where the server genuinely cannot access files. By leveraging browser-side encryption with AES-256-GCM and storing keys in URL fragments, the implementation achieves true zero-knowledge storage. The author's breakdown of streaming encryption and key-commitment mechanisms offers developers a working model for authentic end-to-end file sharing.