Is ByteByteGo Good Platform for System Design Interview? Review

Credit - ByteByteGo

Hello guys, if you are preparing for System Design Interview in 2025 then you may have most likely come across names like ByteByteGo, Alex Xu or System Design Interview - An Insider Guide by Alex Xu, and if you are wondering what they are or you know about them but thinking whether ByteByteGo is worth it or not for System Design and Coding interview preparation then you are not alone?

If you ask me, Yes, ByteByteGo is indeed worth considering for your System Design Interview preparation, because it was created by Alex Xu, an expert with FAANG interview experience and someone who has the privilege to be on both sides of the table.

The platform also offers in-depth coverage of system design topics.

Alex's use of diagrams to explain concepts in detail enhances the learning experience, and most importantly, Alex Xu regularly and new content and updates old ones, for example, he has recently added a section for coding interview patterns on the ByteByteGo website.

ByteByteGo goes beyond theory by providing practical solutions to common system design problems like designing WhatsApp and YouTube. Additionally, the platform offers a structured framework to tackle System Design questions during interviews.

This comprehensive approach, coupled with the author's industry insights, makes ByteByteGo a valuable resource for anyone aiming to excel in System Design Interviews

Now that I have answered your question on whether ByteByteGo is worth it or not, let's dive deep now. In this article, I will provide my detailed review and opinion on ByteByteGo *and its popular *System Design Interview - An Insider's Guide book and recently released Coding interview pattern book by Alex Xu and Shaun Gunawardane.

Though if you are in a hurry and just need a second opinion, I suggest you go for it.

Also, the value the ByteByteGo course provides is much more than the price you pay.** 

It's one of the most comprehensive, up-to-date, and easy-to-learn System design courses I have come across, and I highly recommend it to every Programmer and Software Engineer, irrespective of whether you are preparing for a System Design Interview or not. It will help you to become a better developer in quick time.

It now also contains content on Object Oriented Design, Generative AI System Design, Machine Learning System Design, and even Coding Interview Patterns, which makes the platform even more valuable. On top of that new design and 50% launch offer are simply too good to miss out.

If you have already made your mind, I highly recommend that you join ByteByteGo now to benefit from their current offer.

I first came across Alex Xu and ByteByteGo when one of his tweets on how HTTPS works? Popped me on my timeline on LinkedIn, I liked the way he explained the concept, and his clear diagrams.

After that I started to find more about ByteByteGo and Alex and found that he is also an author of the popular System Design book, called System Design Interview -- An insider's guide Part 1 and Part 2 and since I have always been interested on System design and Software Architecture I started reading them.

The more I read them, the more I become a fan of Alex Xu and his work, and then I found that he also has an online course on System Design on ByteByteGo or Byte Byte Go, whatever you call.

His course is a digital version of both of his books, it covers all the material provided in System Design Interview -- An insider's guide Part 1 and Part 2, but also more stuff as he keeps adding new stuff on this website.

For example, now the website has content of his 8 books, including System Design, OOP Design, Gen AI System Design, Machine Learning System Design, and Coding Interview Patterns.

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What is ByteByteGo? What does ByteByteGo offer?

ByteByteGo is a text-based System Design course that contains lots of detailed illustrations to guide you through how to build complex systems step by step in a way that's easy to understand.

As Alex Xu put it, ByteByteGo or Byte Byte Go is the digital version of his popular System Design Interview -- An insider's guidebook. 

It not only covers all the materials in parts 1 and 2 but also additional material that Alex added only to the online version.

It's similar to Educative's** Grokking Modern System Design For Software Engineers and Managers** course, which is also text-based, but it's a well-thought-out course and covers a lot more concepts.

The first 3 of the 13 chapters are dedicated to Location-Based Services(LBS). Since many of us use location-based apps like OLA, Uber, Grab, Google Maps, etc, it makes it easy to understand how they are implemented and work.

ByteByteGo also covers things like Proximity Services that deal with static locations like Yelp, and the Nearby Friends service, which deals with dynamic locations because people move.

And their deep dive into Google Maps is another useful information, which is a massive Geospatial platform.

What I most like about both book and course is that they discuss various Geospatial indexes (Google S2, Quadtree, Geo Hash, etc), including their tradeoffs; this is something I haven't found covered in other popular System design courses.

But, this is not all; they cover many other popular systems like Payment Systems, Distributed Email Service, and Real-time Gaming Leaderboard, which will surely broaden your knowledge.

Is ByteByteGo worth it for Beginners and Experienced Developers?

Even though the book was designed with System Design Interview in mind, it revisits and explains key computer science concepts with a twist of engineering that is not only useful for system design interviews but also for every programmer and Software engineer who wants to become better at their job.

Both System Design book and ByteByteGo website will help you to better understand why some design decisions are made over others, which makes it ideal for beginners and experienced folks who want to brush up on system design concepts before an interview.

One worth mentioning thing about ByteByteGo and his System design book is Case studies. I like to read case studies that are diverse, engaging, and in-depth, and ByteByteGo fits that bill.

I imagine it was quite a feat to cover quite a wide range of subjects in practical details, while at the same time keeping it crisp and easy to digest, in a 400-ish page book or an online course.

What I like most about ByteByteGo System Design training course is that every single design decision consider the scale of system like small, medium or large In addition all algorithms come with a practical time/space complexity analysis, in some cases it goes deep into the data structure used and how such Data Structure fit into a production ready environment, which is what many people like me liked to see.

You will learn to analyze tradeoffs of packing a quadtree geo-hashed regions into 1GB memory and how it impacts server startup time, otherwise point in the right direction for those willing to deepen their understanding of the just discussed concepts in depth.

All these things make ByteByteGo *and *System Design Interview -- An insider's guide a must-read book for every programmer. All the things you learn are worth the price you pay for the book and the course; it's immensely valuable.

credit - ByteByteGo.com

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Which System Design Problems are solved in this course?

If you are wondering which System design problems are solved in this book or course, and which products are designed and explained, then here is a list of them:

1. How to design YouTube?
2. How to design Ads Aggregation?
3. How to design the Stock Exchange?
4. How to design a Newsfeed?
5. How to design a Gaming Leaderboard?
6. How to design a Mail Server?
7. How to design a Hotel Reservation System?
8. How to design a URL Shortener like bit.ly?

9. How to design Web Crawler?

How to design a Notification System? 

11. How to design a Payment System? 

12. How to design a Digital Wallet? 

13. How to design Search Autocomplete and so on? 

14. How to design a BlockingQueue?

Apart from that, they explain many key System Design concepts and algorithms like consistent hashing, distributed caching, Rate Limiter, Unique ID Generator, as well as a framework for System Design Interview.

Many of these resources are completely free on the ByteByteGo platform, and you can read them to get a feel of the content.

Conclusion

The ByteByteGo System Design course by Alex Xu stands out as one of the most comprehensive and visually engaging resources for mastering system design.

Whether you're preparing for FAANG-level interviews or looking to deepen your understanding of distributed systems, this course offers a structured and digestible learning path.

The blend of high-quality animations, real-world scenarios, and expert explanations makes complex topics easy to grasp.

While the course is not cheap, its value far outweighs the cost—especially if you're serious about leveling up your system design skills. If you prefer self-paced learning with clear visuals and practical insights, ByteByteGo is absolutely worth the investment.

In short, if you want to learn system design the right way, ByteByteGo is a smart choice.

P. S. - ByteByteGo is also offering 50% discount now, you can check here

10 Must Know Topics for System Design Interviews

Disclosure: This post includes affiliate links; I may receive compensation if you purchase products or services from the different links provided in this article.

image_credit - DesignGuru.io

Hello devs, if you have attended technical interviews, then you may know thatthe System Design part is one of the toughest to crack. I think, why so? And the answer I found was that most of the developers are not really familiar with essential System design topics or concepts, and that's what I am going to share in this article.

As I have said before, System design interviews are a crucial part of the hiring process for software engineers and developers, and you must prepare for them; leaving it to chance is not a good idea.

These interviews assess your ability to design scalable and efficient systems to solve real-world problems. To excel in system design interviews, it's essential to have a strong grasp of the fundamental concepts and principles.

In the past, I have shared several system design interview articles like API Gateway vs load balancer, Forward Proxy vs Reverse Proxy as well common System Design problems and In this article, we will explore ten essential system design topics or concepts that will help you prepare for your next interview and impress your potential employers.

By the way, if you are preparing for System design interviews and want to learn System Design in depth then you can also checkout sites like ByteByteGo, DesignGuru, Exponent, Educative , bugfeee.ai and Udemy which have many great System design courses and if you need best system design courses you can also see this article.

10 Essential System Design Topics and Concepts for Tech Interview

To stand out from the competition in system design interviews, it's crucial to have a solid understanding of key concepts that set you apart from other candidates.

By mastering these ten system design concepts, you can position yourself ahead of 99% of candidates and impress interviewers with your expertise.

1. Scalability

Scalability is crucial in system design as it ensures that a system can handle increasing loads and maintain performance. You should understand concepts like horizontal and vertical scaling, load balancing, and distributed systems to design scalable architectures. Those will really help you for tech interviews.

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2. Availability and Fault Tolerance

Designing fault-tolerant systems is essential to maintain availability even in the face of failures. As a candidate, you should learn about replication, redundancy, failover mechanisms, and fault tolerance techniques like backups, checkpoints, and error handling.

For high availability, many company create active- active or active-passive architecture as shown below. 

The best example is cloud computing company like AWS and Azure who has data centers in different part of world and if one goes down then server clients from others.

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3. Data Storage and Databases

Different applications require different types of data storage. You should familiarize yourself with different types of databases like relational databases, NoSQL databases, key-value stores, and columnar databases. Understand their strengths, weaknesses, and use cases.

One of the common questions and concept to understand here is SQL vs NoSQL as they often comes during different questions, here is a nice diagram which highlights the difference between SQL and NoSQL

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4. Caching

Caching helps improve performance by storing frequently accessed data closer to the users. In this topic you should learn about caching techniques, caching strategies, cache eviction policies, and cache coherence to design efficient caching systems.

You should also get yourself familiar with things like cache hit and cache miss and here is a nice diagram from quick reference:

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5. Message Queues and Event-driven Architecture

Message queues enable asynchronous communication between different components of a system. While preparing for this topic you should understand concepts like pub-sub (publish-subscribe) patterns, message brokers, event-driven architecture, and their applications in building scalable and loosely coupled systems.

In the past, I wrote about Apache Kafka vs ActiveMQ vs RabbitMQ which is good starting point to learn about message brokers and Queue.

Here is an nice diagram showing Event Driven Architecture using pub-sub model and point-to-point model :

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6. System APIs and Microservices

This is another popular topic on System design interviews. Microservices architecture allows breaking down complex systems into smaller, independent services.

In this topic you should learn about designing APIs, service discovery, inter-service communication, and managing dependencies to create robust and scalable microservices-based architectures.

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7. Security

Security is a critical aspect of system design. While preparing for this topic you should spend time to understand common security threats, authentication and authorization mechanisms, encryption, and secure communication protocols like SSL/TLS. Be aware of best practices for securing data at rest and in transit.

Learning things like How HTTPS works is also a great question to start with. Here is a nice diagram from ByteByteGo to understand that:

image_credit --- bytebytego

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8. System Performance Optimization

Optimizing system performance is vital for providing a seamless user experience and this is also one thing which interviewer expect form you, especially from senior developers.

As part of this topic you should learn about profiling, load testing, latency reduction techniques, and performance optimization strategies to identify and resolve bottlenecks in your system.

Learning about Database optimization using normalization and index as well as understanding how SQL query work to optimize it is also a great topics to start with

And, if you don't know how SQL query works, here is a nice diagram to understand that:

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9. Design Patterns

Design patterns offer proven solutions to recurring design problems. As a software engineer you should familiarize yourself with design patterns like the Singleton, Observer, Builder, and Factory patterns.

You should also understand when and how to apply them to create scalable and maintainable systems. You should also learn about Microservices design pattern like SAGA, CQRS, Load Balancer, Circuit Breaker, DB Per Microservices, and API Gateway pattern.

Here is a nice design pattern cheat sheet you can print to remember key OOP design patterns for interviews:

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10. Trade-offs and System Constraints

Nothing is perfect and compromise and trade off is what you need in real world to work. System design often involves making trade-offs based on specific constraints.

You should always consider factors like cost, time, available resources, and technology limitations. You should also understand how to make informed decisions based on these constraints without compromising the overall system design.

Knowing things like Big-O notation also helps when you talk about system design algorithms:

Conclusion

That's all about 10 System design topics you must prepare for tech interviews. Mastering these ten essential system design concepts will significantly enhance your performance in system design interviews.

By understanding scalability, fault tolerance, data storage, caching, message queues, microservices, security, performance optimization, design patterns, and trade-offs, you'll be well-prepared to tackle complex design problems and impress interviewers with your comprehensive knowledge.

Remember, practice and hands-on experience in designing real-world systems are equally important, so apply these concepts in practical scenarios to solidify your understanding. Good luck with your interviews and your future endeavors as a skilled system designer!

By the way, if you are preparing for System design interviews and want to learn System Design in depth then you can also checkout sites like ByteByteGo, DesignGuru, Exponent, Educative and Udemy which have many great System design courses and if you need books, you can also see this list of best System design books for interviews.

Difference between @Controller vs @RestController in Spring Boot

Hello friends, if you are preparing for Java and Spring Developer interview then you may have come across "difference between @Controller and @RestController annotation" in Spring Boot and Spring Framework in general. It's one of the popular spring question which I have also mentioned in my list of 25 Spring Framework questions earlier

6 Best Udemy Courses to Learn Agentic AI from Scratch in 2026

credit — Pault Iustzin of LLM Engineer’sHandbook

Hello guys, Agentic AI is quickly becoming one of the most important shifts in modern software development. Instead of single-prompt AI systems, we’re now building autonomous agents that can plan, reason, use tools, collaborate with other agents, and execute multi-step tasks reliably.

In 2026, knowing how to build AI agents with Python is no longer optional for AI engineers, backend developers, or full-stack engineers working with AI-driven products.

Kotlin or Java? Which is Best Programming Language for Android ?

Ever since Google announced @Kotlin as the official language for Android development at Google IO in 2017, programmers who want to become Android developers are in a dilemma.

The big question in front of them is whether they should learn Kotlin or Java.

If you are a complete beginner who wants to learn Android development, then my answer is Java, but if you are a Java developer who wants to jump into the lucrative market of Android app development, then my answer is Kotlin.

I’ll discuss why beginner Android programmers should start with Java and why Java developers should learn Kotlin in this article.

When I say beginners should start with Java, you may be thinking, “What the heck? Kotlin is much more productive, less boilerplate code, and now the official language of Android development, and this guy is suggesting learning Java. I am not gonna fall for it…”

Well, being a Java developer, I may be a little bit biased, but I’ll try to explain the reasons why I suggest a beginner Android developer starting with Java rather than Kotlin.

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Kotlin or Java? Which is better for Android Developers?

The first and foremost thing is that Android development is not everything; as a programmer, you may be starting your career with Android development, but if you start with a well-established language like Java, you become a part of the bigger Java community and market, which directly means more job opportunities.

The second and more important thing is that there is a huge community of Java programmers, which means you can find answers when you are stuck.

This is very important because, as a beginner, you will face a lot of technical problems and you might not know where to head when you are stuck.

When you search Google with a Java problem, you are bound to get answers; the same cannot be said for Kotlin, which is still a new programming language.

There are also more tutorials, books, and courses out there, both free and paid, which can teach you Android development with Java, like this list of Android resources for Java programmers, but there are not many for Kotlin, especially free resources on Android development.

Things will definitely improve over time when more and more programmers start using Kotlin, but I doubt it can ever touch the popularity and adoption of the Java programming language.

That’s why I suggest, a beginner programmer who wants to become an Android developer should start with Java, rather than Kotlin.

However, that’s not a hard and fast rule; if you prefer learning Kotlin rather than Java due to productivity reasons and are mostly focused on Android development, then you can sure start with Kotlin, and Kotlin: The Mega Course – All-in-One is a good place to begin.

But, once you know Java, your journey to Kotlin will also be easy and smooth because Kotlin is 100% interoperable with Java. It compiles into Java bytecode and runs on JVM.

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Java Programmers Should Learn Kotlin

Now, coming back to the second set of programmers who wants to learn Android development: our fellow Java developers. For them, I think it's best to learn Kotlin because it really improves productivity.

A class that takes 50 lines of code in Java can really be written in just one line in Kotlin. It can help you avoid all boilerplate code, like you don’t need to specify getters and setters, equals(), hashCode()or toString() methods. Kotlin can generate all that by itself.

Here is a nice comparison between Kotlin and Java in terms of productivity and lines of code to write similar stuff:

If you don’t know, Kotlin was developed by JetBrains, the company behind one of the most popular Java IDEs, IntelliJ IDEA. They were a Java shop and developing IDEs like IntelliJ IDEA, PyCharm, and ReSharper, all in Java, and built Kotlin to improve their productivity, but at the same time, they cannot rewrite all their code in Kotlin, so that’s why they made Kotlin fully interoperable with Java.

Because Kotlin generates Java bytecode, you can use your favorite Java frameworks and libraries in Kotlin and your Java friends can also use any Kotlin framework you develop.

Even a major Java framework like Spring has started supporting Kotlin from Spring 5. If you don’t know Spring and want to learn Spring Boot 4, Spring 7 & Hibernate for Beginners, check that out.

Even though currently, almost all @android code, examples, and apps are in Java, it will change in the future because Google has declared Kotlin as the official language for Android app development.

Many companies have already started using Kotlin for their Android app development, and that’s the main reason I think Java developers should learn Kotlin.

If you decide to learn Kotlin Programming language, then Kotlin for Android: Beginner to Advanced is also a great place, to begin with. It’s a no-nonsense course for Java developers which will help you to get going with Kotlin in no time.

You don’t need to start with things like what a variable and object are, as this course has the right pace and depth for Java developers as compared to other beginner Kotlin courses for Android development.

If you prefer books, then Kotlin in Action is also not bad. You can learn about all the essential features of Kotlin, e.g. var vs val, data keyword, and functional programming all by yourself.

That’s all about whether Android developers should learn Kotlin or Java. As I said, if you are a complete beginner who wants to start your career as an Android developer, you’d better start with Java.

You will not only get up to speed in no time, but you would have better community support, and knowledge of Java will help you a lot in the future. It will also help you to learn Kotlin in the future.

If you are a Java developer, then you’d better start learning Kotlin to not only improve your productivity but also help you become part of a lucrative niche of Java developers who know Kotlin, which may give you a competitive edge in the job market. It’s also one of the 3 JVM languages Java developer should learn on my list.

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Thanks for reading this article so far. If you liked it then, please share them with your friends and colleagues. If you have any questions or feedback, then please drop a note.

P. S. - If you want to learn a valuable skill like Kotlin, then I highly recommend you check out these best Kotlin courses from Udemy, which are both comprehensive and very engaging. You can use this course to learn Kotlin for server-side Java development and mobile app development with the Android platform.