The Y Combinator Database - The definitive database of YC companies with all the metrics
Startup Stash - A curated directory of 400 resources & tools for startups
Startup School - How to start a startup, by Y Combinator
GitHub Student Developer Pack - The best developer tools, free for students.
Y Combinator Companies - Interactive list of all 1000+ YC companies
ProppyJS - Functional props composition for UI components (React & Vue)