Show OS: Universal Uploader – Zero-dependency, stream-based file uploading with transparent XHR fallback

Hey everyone,

I wanted to share an open-source library I’ve been developing to solve a persistent issue in frontend file ingestion: handling large-file uploads efficiently without blocking the main thread, consuming excessive client-side memory, or introducing heavy npm dependencies.

The core architecture leverages Fetch Duplex streams combined with Web Streams API to achieve constant memory usage during large file transfers. For browsers lacking full duplex stream support (such as Safari), it seamlessly switches to an automated chunked XHR fallback at runtime.

Constant Memory Footprint: Streams large chunks sequentially using Fetch duplex streaming where supported.

Intelligent Runtime Fallback: Detects capabilities instantly and falls back to a robust, chunked XMLHttpRequest pipeline to ensure cross-browser compatibility (including Safari).