class SystemDesign {
scalability: true,
performance: 99.9%
}interface Interview {
duration: 60min,
difficulty: adaptive
}Practice with Alex, an AI that interviews like a Principal Engineer. Get instant feedback, track progress, and land your dream role.
Hi! I'm Alex, your AI interviewer today. Let's design a distributed messaging system like WhatsApp. Can you start by gathering the requirements?
Sure! Let me understand the requirements:
**Functional Requirements:**
• One-to-one messaging
• Group messaging (up to 500 users)
• Message delivery status
• Online/offline status
• End-to-end encryption
Good requirements gathering! Now, let's discuss the high-level architecture. How would you design the system to handle 1 billion daily active users?
Let's design WhatsApp. Can you start by gathering the requirements?
Sure! Let me understand the requirements first...
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Principal Engineer at Tech Co.
Question:
Design a URL shortener like bit.ly
Let's aim for 100M URLs per day with < 100ms latency
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System design interviews are unique - unlike coding problems that have clear solutions, they are open-ended conversations that require a human-like interaction to practice effectively. Instead of paying hundreds of dollars for mock interviews with real people, we created Alex to provide that same interactive, adaptive experience at a fraction of the cost. Alex gives you unlimited practice opportunities with a consistent, high-quality interviewer available 24/7.
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