System Design Refresher

System Design Refresher is a free study companion for software engineers preparing for system design interviews. WHAT'S INSIDE • 30+ system design articles covering distributed systems, databases, caching, and more • Engineering blogs from top tech companies (Google, Meta, Stripe, Airbnb, and more) aggregated in one place • AI-powered flashcards with spaced repetition • Ask AI to summarize or explain any article in plain language • Favorites, reading progress tracking, and custom RSS feeds FEATURES • Works offline — articles download for reading without internet • Dark mode, font customization, and text size controls • Face ID / Touch ID lock for privacy • Sign in with Google or Apple, or use as a guest with no account required