Uppy - The next open source file uploader for web browsers
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Filestack - Simple file uploader and robust APIs for uploading, transforming, and delivering any file into your app. Filestack is a collection of tools and powerful APIs that make it simple to upload, transform, and deliver content.
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CDNify - Accelerate your apps and websites with the CDNify content delivery network. Superfast, simplified and affordable CDN for developers, startups and agencies.
tus.io - File Uploads