System design interviews will never crack until you know this hack !

If you’re a working professional targeting for senior roles at PBCs then


Here's a simple approach to crack it:

𝗔𝘁𝘁𝗶𝘁𝘂𝗱𝗲: Stay playful and collaborative.

𝗦𝗰𝗼𝗽𝗲: Ask targeted questions to narrow down the scope.

𝗖𝗼𝗺𝗽𝗼𝗻𝗲𝗻𝘁𝘀: Understand and use the main infrastructure components like LEGO pieces.


Here's a quick overview of the 10 main elements to consider during a system design interview. What you discuss will depend on your prompt.

𝟭. 𝗙𝗲𝗮𝘁𝘂𝗿𝗲𝘀 - Start with the main features of the system. For example, if asked to design Twitter, list its key features. This helps ensure you're aligned with the interviewer.

𝟮. 𝗨𝘀𝗲𝗿𝘀 - Consider the types of users, usage patterns, and growth rates. Identify peak times and regions.

𝟯. 𝗗𝗮𝘁𝗮 𝗠𝗼𝗱𝗲𝗹 - Decide between relational and NoSQL databases based on your use case. Plan your tables, indexing, and replication strategies.

𝟰. 𝗚𝗲𝗼𝗴𝗿𝗮𝗽𝗵𝘆 & 𝗟𝗮𝘁𝗲𝗻𝗰𝘆 - Reduce latency with servers in different regions. Use CDNs to serve content faster.

𝟱. 𝗦𝗲𝗿𝘃𝗲𝗿 𝗖𝗮𝗽𝗮𝗰𝗶𝘁𝘆 - Determine CPU, RAM, and storage needs. Plan for vertical and horizontal scaling.

𝟲. 𝗔𝗣𝗜𝘀 & 𝗦𝗲𝗰𝘂𝗿𝗶𝘁𝘆 - Choose between REST, GraphQL, or gRPC for your APIs. Address security concerns and implement rate limiting.

𝟳. 𝗔𝘃𝗮𝗶𝗹𝗮𝗯𝗶𝗹𝗶𝘁𝘆 / 𝗠𝗶𝗰𝗿𝗼𝘀𝗲𝗿𝘃𝗶𝗰𝗲𝘀 - Ensure high availability with redundancies and fault tolerance. Use tools like Kubernetes if needed.

𝟴. 𝗖𝗮𝗰𝗵𝗶𝗻𝗴 - Speed up reads with caching at various layers. Use appropriate eviction policies.

𝟵. 𝗣𝗿𝗼𝘅𝗶𝗲𝘀 - Use load balancers and reverse proxies for better availability and security.

𝟭𝟬. 𝗠𝗲𝘀𝘀𝗮𝗴𝗶𝗻𝗴 - Choose the right messaging protocols (TCP/UDP) and tools (Kafka, RabbitMQ) based on your needs.

You can check these resources for Coding interview Preparation

All the best 👍👍