How to Answer System Design Interview Questions (Complete Guide)

The system design interview evaluates your ability to design a system or architecture to solve a complex problem in a semi-real-world setting. It doesn’t aim to test your ability to create a 100% perfect solution; instead, the interview assesses your ability to:

- Design the blueprint of the architecture
- Analyze a complex problem
- Discuss multiple solutions
- Weigh the pros and cons to reach a workable solution

0:00 - Introduction
0:20 - What is a system design interview?
1:24 - Step 1: Defining the problem
1:43 - Functional and non-functional requirements
2:40 - Estimating data
3:10 - Step 2: High-level design
3:30 - APIs
4:00 - Diagramming
4:20 - Step 3: Deep dive
5:10 - Step 4: Scaling and bottlenecks
6:20 - Step 5: Review and wrap up

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[Tempeck]

1. **Define the Problem Space:**
- Understand problem and define scope.
- Clarify functional and non-functional requirements.
- State assumptions and decisions explicitly.

2. **Design the System at a High Level:**
- Design APIs to define how clients access system resources.
- Consider request parameters, response types, and communication between client and server.
- Create a high-level design diagram to illustrate system architecture.

3. **Deep Dive into the Design:**
- Examine system components and relationships in detail.
- Consider non-functional requirements' impact on design choices.
- Present different design options with pros and cons.

4. **Identify Bottlenecks and Scaling Opportunities:**
- Assess system's ability to operate under various conditions and support growth.
- Address single points of failure, data replication, global service support, and scalability.
- Consider concepts like horizontal sharding, CDN, caching, rate limiting, and databases.

5. **Review and Wrap Up:**
- Summarize major decisions with justifications and trade-offs.
- Ensure design satisfies all requirements.
- Identify directions for further improvement.

[paulm.]

I have a technical interview and for the first time ever, I've been asked to do a System Design Exercise as part of this process. This video really breaks down all the questions I have into manageable components that have really alleviated a lot of my concerns and have me prepared to handle that portion a lot more easily than I would have otherwise. Killer video with excellent and succinct communication. Thanks for this.

[shinygoomy]

I got a system design interview tomorrow and I can't do the deep dive part... There's too much random stuff to memorize that I have never used before. Anyone got any tips for taking a SD interview when you don't know anything about SD? Ie. How can I fail in the most elegant way possible?

[GengoSenmon]

Great video, especially the part about horizontal sharding, CDN, caching, rate limiting, and databases

[adamjenkins]

Such a clear and concise explanation! Thank you! I hope when AI teachers are created in the future they model them after people like this.

[narsing]

So amazing video of explain the concepts in very simple terms. great lady.

[ambikeya_tech]

Great insights! Your comprehensive guide offers valuable strategies for tackling system design interviews effectively.

[abomosb]

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I also really enjoy your teaching style. You are so passionate about the subjects you teach, and it's clear that you care about your students. You are also very engaging and entertaining to watch, and I never feel bored when I'm watching your videos.

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Sincerely,
MOHAMED

[waffle]

Not every company is going to make you remember stuff, most of the time it's open note / Google search permitted. They do that to also gauge how well you'll do in research which is what you'll do most of the time.

[nickroberts]

Really great explanation, Neamah! thank you

[elitea]

that's why I hate getting interviews for soft dev why do they make it hard? Not only that they make it so there is many stages, I hate this whole process. Wish me luck I got a interview with a big bank tomorrow AND I AM DOING ALL THIS LAST MINUTE

[pradeeppatra]

Nice video which covers complete system design in 5 steps, Awesome!❤

[Casanovajosh]

Valuable info! Thank you for sharing!!

[soniahandle]

Can you give some examples of functional vs nonfunctional requirements in the context of system design?

p.s. - Great video, thank you for sharing :)

[ge_song]

I see a lot of overlapping between step 3 and 4. Should they be merged into one?

[PrinceDavid]

Great video on system design prep. Although I actually had a long session today that lasted an hour and fifteen minutes!

[rahulvashishth]

which tool do you use for video editing and diagrams?

[dtvind]

Ise eks and hpa to solve app scalability

[ddtalkuntold]

How product owner will know about syste design, just you are giving very shallow info here . As a product owner you dont work on system design and you are not expected to work on this .