What is the best way to practice mock system design interviews?

The best way to practice mock system design interviews is to use a structured platform like System Design Lab. It provides real interview questions (design URL shortener, design Twitter, design Netflix), an interactive diagram builder, an AI interviewer that asks follow-up questions, and detailed feedback on your architecture, scalability decisions, and trade-offs — exactly like a real FAANG interview.

How do I prepare for a system design interview?

To prepare for a system design interview: (1) Learn core concepts like distributed systems, caching, databases, sharding, and message queues. (2) Practice drawing architecture diagrams under time pressure. (3) Take knowledge quizzes to test your understanding. (4) Do mock system design interviews with AI feedback to get comfortable explaining your decisions. (5) Review community solutions to see how others approach the same problems. System Design Lab covers all five steps in one platform.

What system design interview questions should I practice?

Common system design interview questions include: Design a URL shortener, Design Twitter/social media feed, Design Netflix/video streaming, Design a distributed cache, Design a rate limiter, Design a notification system, Design a ride-sharing app like Uber. System Design Lab offers 30+ curated problems covering all major categories asked at FAANG and top-tier tech companies.

Is there a free mock system design interview tool?

Yes — System Design Lab offers a free 7-day trial with access to 3 mock system design interview problems, all learning modules, all quizzes, and community solutions. No credit card required. Premium (₹999 for 90 days) unlocks unlimited problems and AI interviewer access.

How does System Design Lab's AI interview feedback work?

After you submit your system design, the AI evaluates your written explanation and architecture diagram together. It scores you on completeness, scalability, fault tolerance, and clarity, then gives you specific, actionable feedback — similar to what a senior engineer would say after your interview. You can also chat with an AI interviewer in real-time during your attempt.

Blob & Object Storage | Learn | System Design Lab

A blob (Binary Large OBject) is any opaque chunk of bytes — an image, video, PDF, ML model checkpoint, log archive, or database backup. Object storage is the system designed to hold billions of these blobs cheaply and durably, exposing them over a simple HTTP API. Amazon S3, Google Cloud Storage, and Azure Blob Storage are the canonical examples.

The core idea: instead of mounting a disk and navigating directories, you PUT a blob under a unique key and later GET it back by that key. There is no filesystem to manage, no capacity to provision, and no servers to patch — the storage scales effectively without bound and you pay only for what you store and transfer.

Why interviewers love it

Almost every large system stores user uploads, media, or backups — so object storage shows up in nearly every design.
It forces a clean discussion of the metadata-vs-blob split: store the bytes in object storage, store the searchable metadata (owner, key, size, content-type) in a database.
It opens the door to high-value follow-ups: presigned URLs, CDN serving, storage tiers, and durability math.

What Is Blob & Object Storage?

Why interviewers love it