System Design Interview Questions & Tips for Senior Engineers

About System Design Interviews

If you’re a mid-level or senior-level software engineer, regardless of where you interview, you will get asked at least a few system design questions. Most companies will ask system design questions during the onsite, but some may include a system design component in their technical phone screen (more likely if they’re a startup rather than a FAANG).

System design interview questions fall, by and large, into the following 12 categories:

APIs
Databases (SQL vs NoSQL)
Scaling
CAP theorem
Web authentication and basic security
Load balancers
Caching
Message queues
Indexing
Failovers
Replication
Consistent hashing

That’s a long list, and system design is a really broad topic. Rather than trying to summarize everything you need to know about these types of interviews in a few paragraphs (an impossible task), we’ve written the best guide to system design interviews out there.

By the way, many people believe that in order to pass a FAANG system design interview, you have to have professional experience with distributed systems. We’ll show you that that’s categorically false, and that with the right preparation, you don’t need to fall into the catch-22 of having to have worked at a FAANG in order to get a job at a FAANG.

Check out our in-depth guide to system design, developed by the best interviewers in the industry, directly from their experience in thousands of technical interviews:

System Design Interview Replays

Google Interviewer

Design Facebook Events

The Grey Dictaphone,aGoogleengineer, interviewed Absurd Bandit](/content/mocks/google-system-design-design-facebook-events/index.html)

Meta Interviewer

Design Live Comments

Digital Cactus,aMetaengineer, interviewed Utilitarian Lemur](/content/mocks/facebook-system-design-design-live-comments/index.html)

FAANG Interviewer

Photo sharing service

Platinum Lambda,aFAANGengineer, interviewed Orthogonal Warrior](/content/mocks/faang-system-design-photo-sharing-service/index.html)

Google Interviewer

Design YouTube Recommendation System

Doctor Malamute,aGoogleengineer, interviewed Hyper Taco](/content/mocks/google-system-design-youtube-recommendation-system/index.html)

Amazon Interviewer

Video upload API

Hot Gyro,anAmazonengineer, interviewed Wicked Gyroscope](/content/mocks/amazon-system-design-video-upload-api/index.html)

Amazon Interviewer

Calendar System

Phantom Dictaphone,anAmazonengineer, interviewed The Mighty Platypus](/content/mocks/amazon-system-design-calendar-system/index.html)

[...] (replays continue in similar format)