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You can reset your password from the sign-in screen by selecting "Forgot Password". A magic link will be sent to your registered email.
SD Primer offers a free tier with daily MCQ questions. Premium features like the System Design Lab, advanced patterns, and AI-guided challenges are available with a subscription.
Your streak increments each day you complete the daily question. Missing a day resets your streak. Your longest streak is always saved as your personal record.
Currently, SD Primer requires an internet connection. Offline mode is on our roadmap.
Our smart queue uses spaced repetition to resurface topics at optimal intervals. You'll see due reviews first, then new questions, then practice material.
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