The Easiest Concurrency Problem - Race Condition

Drawing from my own experience of feeling despondent when trying to implement practical code during my first MSA transition—despite knowing the theory—I will help you grow into a developer who guarantees perfect data consistency amidst any system failure by directly rolling back daunting compensation logic through 9-step practical patterns and AI Agent coding.

This course goes beyond simple CRUD-level database usage to help you acquire PostgreSQL skills necessary for the AI era from a practical perspective. Based on AI development experience in Silicon Valley, you will learn step-by-step how to design and utilize JSON, indexes, transactions, and even pgvector in real-world services, while mastering methods to solve complex data structures and performance issues.

The biggest challenges in operating batch systems that process millions of records are performance degradation and the difficulty of recovery in the event of a failure. These issues cannot be solved with simple loops or poor design. Based on my experience of reliably processing large-scale data in real-world service environments, this course covers the structure and operating principles of Spring Batch and provides design methods to achieve both performance and stability. Moving beyond simple functional descriptions, this course will help you develop fundamental data processing problem-solving skills through batch architectures that can be applied immediately in practice.

Many backend developers use Redis, but in reality, they often use it merely as a simple cache server. There are many cases where developers know the Redis data types but don't know how to apply them in practice, lack experience implementing real-world patterns like distributed locks or rate limiting, or fail to understand Redis from a backend architecture perspective. I also had the experience of pondering how to utilize Redis in a high-traffic environment while developing actual services. This is because knowing simple commands is entirely different from solving service problems with Redis. This course starts with the basic concepts and data structures of Redis and progresses through learning by implementing core patterns used in actual backend services step-by-step. In particular, you will learn how to solve the following practical problems using Redis: Caching (Cache-Aside) strategies to reduce server load, Distributed Sessions (Session Store) to share login states, Distributed Locks to solve concurrency issues, Rate Limiting to prevent API overload, and Real-time Ranking Systems (Leaderboards) for large-scale users. All hands-on exercises are conducted in a real API server environment based on Python FastAPI. Rather than just learning simple CLI commands, you will understand how Redis is used in backend systems by implementing it yourself. Through this course, you will be able to utilize Redis not just as a simple cache, but as a core tool for designing backend architecture.

Regardless of the field! This is a lecture that covers the core fundamentals that developers must know in practice in an easy + code-oriented way. I highly recommend this lecture to all junior developers and job seekers who want to grow.

This course proceeds in stages where you learn and apply necessary knowledge while building infrastructure, similar to real-world practice.

This is a practical, hands-on course designed so that even SQL beginners can start easily and apply it right away. ✨ Learn to pull data with SELECT, connect with JOIN, organize with GROUP BY, and more— master only the most frequently used features in real work, in an easy and fun way! 📊 We minimize complex explanations and focus on realistic examples that make you think, "Ah, this is why SQL is important!" 💡 Data analyst, developer, data engineer… Whatever path you choose, SQL is an essential skill. 🚀 With this one course, solidify your fundamentals and develop the data intuition to solve problems on your own in real-world situations! 🔥 Start right now. This is the easiest first step into the world of data! 🌍💙

You can learn about the core functions of MySQL and how to effectively use them in your work. You can also gain a new understanding of important parts that you have been using for a long time and have overlooked, and gain in-depth database knowledge.

Building your own emotional diary service with Spring AI + React It's time for our 4th project with Neo + Essential!

I'll show you how to use Redis effectively, along with its precautions and best practices, using real-world examples from actual work environments and well-known case histories.

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.

This course takes you from the fundamentals to advanced, real-world container workflows using Docker and Kubernetes. You will start by learning containers from the ground up, understanding how Docker works and why it is widely used in modern DevOps environments. You’ll run Docker, Docker Compose, and Kubernetes locally to improve software development, testing, and deployment workflows.

This is a full-stack hands-on course where you will implement a ChatGPT clone from scratch. From Spring Boot server to React frontend | Neo + Essential This is not just a course where you simply follow along with the code; it guides you through actual service deployment so you can build a high-quality AI chatbot service.

This course includes both server (Java+Springboot) and front-end (React, ReactNative, Flutter, Android, iOS) development. Experience building a full-stack bulletin board with this course.

Learn Springboot + NextJS RestAPI Board Creation Faster Than Anyone! Develop a CRUD server with Springboot and create your own board with NextJS!

Extract and utilize data through Oracle 18c and become a database expert!

Learn Springboot + iOS RestAPI Board Creation Faster Than Anyone Develop a CRUD server with Springboot and create your own board with iOS!!

This is a Redis course created with a current Kakao interviewer. It covers everything from data structure practice (String to Sorted Set) to Sentinel and Cluster configurations, helping you build design rationales that work in both interviews and real-world practice.

Through this course, you can learn about Docker and configure a CI environment.

✅ 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

A beginner's guide to SQL coding! We'll teach you the secrets of writing, interpreting, and validating SQL.