From Kotlin to Spring Security

React is the most popular modern front-end framework, but it is difficult to learn. To solve this problem, Hook was introduced. This lecture will help you learn React easily using Hook.

Flask is widely used as a Python backend framework. Flask_SQLAlchemy is a database orm used in Flask. If you know Flask_SQLAlchemy, you can do web development with concise code.

This is a SQL lecture designed to help marketers learn SQL easily. We introduce the essential SQL grammar and analyze real data obtained from Kaggle.

This lecture introduces and solves the Qualification Round 1st problem of Google Codejam, a Google algorithm competition.

Tensorflow uses a complex graph structure even for simple arithmetic. Why? Because Tensorflow needs derivatives when performing Gradient Descent. Graph structure is a means to easily derive those derivatives. I've mathematically explained why.

This is a friendly explanation of things that beginners of Spring Boot and Kotlin will encounter while developing web from a beginner's perspective.

CUDA is a GPU programming language. It is a language that was created by modifying C and C++, so anyone who is a C or C++ developer can easily approach it. However, you must understand the characteristics of GPU machines and CUDA programming. This course understands GPU machines and writes CUDA to execute matrix multiplication, which is the basic operation of deep learning. Through this course, you will be able to handle GPU programming skillfully.

This course explains reinforcement learning without math. You can learn the concepts easily and clearly. In addition, you can implement and run an actual tic-tac-toe game by coding RLkit, which is written in Python, the most accessible language.

Spring CRUD Starting with the Price of Chicken Start server development with the price of chicken!

Through this lecture, you can learn about the characteristics and background of the Kotlin language, grammar and operation principles, usage examples, and things to be careful of when using Java and Kotlin together.

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

Learning about various communication techniques and understanding their differences helps you develop the ability to select and implement the most appropriate communication method.

You can try using jOOQ, a data access technology, and experience Spring development with Kotlin.

Kotlin Programming Language, which you can learn by practicing with 76 examples. You have to develop in Kotlin starting tomorrow, but you don't have time to study the grammar? Let's quickly learn all the grammar of Kotlin with the examples provided in this lecture.

Understanding Spring Boot + React.js Login (+Social) Service is a course designed to help you deeply understand the authentication flow between frontend and backend, by directly implementing a practical login system that includes JWT-based authentication and social login (Kakao/Google). The frontend is built on React.js, and the backend on Spring Boot, enabling you to learn step by step the practices used in real service environments, such as the Access Token + Refresh Token approach, user state management using HttpOnly Cookie and Redux, Role-based authorization, and social login integration.

Have you ever wondered "how" the many Java libraries and frameworks you use provide this functionality? In this course, learn how to manipulate various codes or objects provided by Java and take your Java skills to the next level.

Did you give up while studying Spring? Even complete beginners new to coding and non-majors can make it from JSP to Spring Boot without giving up - we'll open the path to Spring Boot for you.

I've created an 'Introduction to Elasticsearch' course that even non-majors can easily understand and apply directly in real-world situations!

This course is a practical program where you will master Kotlin-based AI agent development by building your own coding agents. Using Koog, an AI framework built with Kotlin, you will learn step-by-step how to implement coding agents similar to Claude Code, Cursor, and Junie. Koog is more than just a simple server-side framework; it integrates seamlessly with Spring and offers the scalability to connect with various environments—including Android, iOS, Desktop, and Web—through Kotlin Multiplatform (KMP). By building intelligent agents that can read, analyze, modify, and generate code, you will gain hands-on experience in AI agent architecture, strategy, context handling, and tool integration.

Spring AI + JPA + MySQL Premium Reservation Agent Backend Development with 'Autonomous Behavior' Beyond Chatbots to Agents: The Definitive Guide to Tool Calling and Prompt Engineering

Experience the power of Type Safe SQL with jOOQ!

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

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

This is a Kotlin coroutine lecture by the author of "The Definitive Guide to Kotlin Coroutines." This lecture covers everything from the basics to the core of coroutines. It provides various visual materials and clear explanations to help anyone easily understand asynchronous programming using coroutines.

# Building an 'Intelligent Collaboration' Expert Agent Team Using Spring AI Router Pattern + RAG + MCP Beyond Single Agents to Architecture: The Definitive Guide to Router Pattern and Agent Isolation Design

Building Your Own Emotional Diary Service with SpringAI + React This is the 4th project time creating together with Neo + Essential!

Kotlin mastery via virtual payment server course.