System Design Refresher vs Syswise

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

Answer one system design question a day. Read why the answer is right. Close the app. Syswise is a question bank with a path running through it. You start on scalability basics and work forward: caching, queues, sharding, consistency. Each unit is a short session of multiple choice questions taken from real interview scenarios, and every question ends with a written explanation of the correct answer and of the ones you did not pick. Sessions run about ten minutes. That is deliberate. Nobody learns distributed systems in a weekend, but you can keep the concepts warm until the interview. WHAT IS INSIDE A path with sections and checkpoints, so you always know what comes next. Four practice modes: review your mistakes, drill your weakest topics, spaced cards that have come due, and a daily challenge. A readiness score built from your own practice, broken down by average mastery, weakest quarter and topic coverage. A streak, a daily goal and a league, if that is what gets you to open the app. WHO IT IS FOR Engineers with a system design round on the calendar. Also anyone who has been hand waving about caches and queues for years and would rather stop. PREMIUM Premium turns your weak areas into an ordered 7 day plan and lifts the session uptime limit. The path itself is free, and the uptime limit resets on its own if you would rather wait. Premium is an auto-renewing subscription, offered weekly and annually. Premium Weekly is 4.99 USD per week and Premium Annual is 39.99 USD per year. Payment is charged to your Apple ID account at confirmation of purchase. The subscription renews automatically unless you turn off auto-renew at least 24 hours before the end of the current period. You can manage or cancel it in your Apple ID account settings. Privacy policy: https://syswise.app/privacy-policy Terms of Use (EULA): https://syswise.app/terms-of-use