Things Clone Coding Doesn't Tell You (System Theory and DB) Part 1

Let's systematically design the backend using the domain-driven development (DDD) method and apply it to microservices!

Take advantage of TypeScript's features!

Learn how to use Cypress to auto-login and auto-purchase features

Master React rendering principles and optimization to apply them in real-world situations and prepare for interviews!

Master the complexities of React development, including custom hooks, TDD, the context API, refactoring, and complex state management.

Learn the easy and fun story of SQL Server operations from a Microsoft Certified Trainer! We explain core operational technologies that you can learn and use right away, and that are truly needed in the field, step by step so that even beginners can easily understand.

Make the most of relational database systems!

# Silicon Valley Internship That Won't Get Cut Even in the AI Era & Complete Course on 30 Big Tech System Designs & Open Source Practical Contributions All students who submit course missions can apply for an AI startup internship in Palo Alto, USA, with exemption from document screening and guaranteed interview opportunities. This course involves designing and scaling 30 real-world system designs based on big tech cases including Netflix, Tesla, Meta, and Tinder. Finally, you'll design your own service from architecture → DB → scaling, contribute to an actively operating open source AI coding agent project (achieving 1.8k downloads per week) to complete your portfolio, and finalize your resume.

Learn common components of global-scale services through popular papers, books, and articles.

You can learn how to solve concurrency problems, how to tune procedures, and how to speed up query execution. You can also learn various know-hows such as common mistakes and problems that occur in practice. (The only refactoring lecture in the world)

This course provides a step-by-step learning path, ranging from the fundamental usage of MySQL to advanced techniques required in real-world production environments. It covers a wide range of topics, including data modeling techniques based on various case studies and practical data, evaluating the effectiveness of Foreign Key designs, analyzing Google Calendar schema DDL, and modern DDL design principles. Through this course, you will gain an in-depth understanding of how to utilize MySQL as a core system component rather than just a simple database.

I will transform the Engineer Information Processing written exam (Subjects 1–5) from a "test you solve by memorizing" into a "test where you connect clarified points directly to your score." This is an ultra-compressed lecture designed to help you grasp the entire flow within 3 days. It extracts only the core concepts repeated in past exams, structured to be understood even if viewed right before the test. The course is designed for short-term success by clearly distinguishing between frequently confusing concepts, trap points in multiple-choice options, and what needs to be memorized versus what only needs to be understood. "I'm short on time, but the scope is too broad." "I feel like I know the material when reading the book, but I keep getting the questions wrong." This lecture is for students facing these exact challenges.

Not only developers, but also planners and data analysts learn databases step-by-step, starting from SQL basics.

This lecture comprehensively organizes the content that would be good for those who want to get a job as a new Spring Java backend developer, especially those who are about to have an interview.

✅ Out of the entire series (1) ~ (7), (5) operating system, user interface, database ✅ CS101 series lectures - From basic computer theory to the latest practical examples - Provides a wide range of basic knowledge