Ace the System Design Interview with Real-World Architectures Course guide
System Design Interview Prep: 13 Real-World Architectures
Prepare for system design interviews with 13 real architectures: proximity service, Google Maps, message queues, payments, S3 and more. Free videos.
Ace the System Design Interview with Real-World Architectures prepares you for system design interviews by walking through how 13 real, large-scale systems are designed from the ground up. It is for software engineers preparing for senior or backend interviews, and for developers who want to strengthen their architecture skills with concrete designs rather than abstract theory.
Each module takes one interview-style problem, such as a proximity service, a nearby friends feature, Google Maps, distributed message queues, a payment system or a stock exchange, and works through requirements, design decisions and trade-offs. The course has 14 videos, about 6.9 hours in total, free on YouTube and listed on the system design interview course page.
Who this course is for
- Software engineers preparing for system design rounds, especially for senior, backend or platform roles.
- Developers moving towards architecture who want to see how real systems handle scale, reliability and performance.
- Engineers who freeze in open-ended interviews and want a structured way to analyse requirements and explain decisions.
The catalog marks it Advanced. You should already understand basic web services, databases and APIs. The course builds on that knowledge rather than teaching it.
What you will learn
The course description lists the core concepts as scalability, reliability, performance, databases, caching, messaging, APIs and distributed systems. They come up again and again across these groups of designs:
1. Location-based systems. Proximity Service, Designing a Real-Time Nearby Friends Feature and Google Maps Architecture Deep Dive. Location data is a classic interview area because it forces you to think about how to search and update data that changes in space and time.
2. Messaging and data pipelines. Master Distributed Message Queues for System Design Interviews, Design a Metrics & Alerting System That Scales and Design a Real-Time Ad Click Aggregator. These designs show how systems move and aggregate huge volumes of events reliably. The message queue module is one of the longest in the course.
3. Booking and communication. How Hotel Booking Systems Prevent Double Bookings and How a Distributed Email Service Actually Works. Preventing double bookings is a sharp test of how well you understand consistency.
4. Storage and real-time ranking. Designing Amazon S3-Style Object Storage and Real-Time Gaming Leaderboard Architecture cover storing data at massive scale and keeping fast-changing rankings up to date.
5. Money and markets. How Payment Systems Actually Move Money, How Digital Wallets Handle Millions of Transfers and Design a Real Stock Exchange Like NASDAQ. Financial systems raise the stakes on correctness and reliability, which is why they make some of the hardest interview questions. The digital wallets module is the longest in the course, at about 39 minutes.
How the course is organised
There are 14 videos and about 6.9 hours in total:
- Video 1: a course overview of the 13 real-world architectures.
- Videos 2–14: 13 numbered deep dives, each about 26–39 minutes long and each covering one complete system.
The modules are self-contained designs, so you can watch them in order or start with the systems most relevant to the companies you are targeting. Watching in order is still a good default if you have time.
How to study it step by step
- Watch the overview to see all 13 systems and choose your priorities.
- Before each module, try the design yourself for 15 minutes. Write down requirements, a rough estimate of scale and a simple diagram. Then watch and compare.
- Take notes in a fixed template: requirements, high-level design, data storage, scaling choices and trade-offs. This mirrors how you should structure a real interview answer.
- Explain each design out loud after watching, as if to an interviewer. Speaking clearly is half of the system design round.
- Link the designs together. Look for building blocks, such as queues, caches or databases, that show up in more than one design, and note how each system uses them differently.
- Do a mock interview with a friend using one system you have not studied, and use the same template.
This course currently has no Skills Pragati hands-on lab guide, practice simulation or mock exam.
Frequently asked questions
Is the system design interview course free?
Yes. All 14 videos are free on YouTube. You can follow them from the course page.
How long does it take?
About 6.9 hours of video. If you attempt each design before watching and then review it, one or two modules a week over six to eight weeks is a realistic plan.
Is it suitable for beginners?
It is rated Advanced. It suits engineers who already build services and want interview-level depth. Newer developers can still learn from it, but should expect to pause and look up concepts along the way.
What else should I prepare for interviews?
System design is usually one round among several. Data Structures And Algorithms For Interview Preparation covers coding rounds, and Interview Fundamentals and Resume helps with the rest of the process.