The Y Combinator Database - The definitive database of YC companies with all the metrics
Uppy - The next open source file uploader for web browsers
Startup School - How to start a startup, by Y Combinator
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.
Y Combinator Companies - Interactive list of all 1000+ YC companies
Uppy.io - Next open source file uploader for web browsers