Distributed Transaction Patterns from an MSA Perspective, Explained by a Kakao Interviewer

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.

Most developers are still stuck on Batch and CronJobs when it comes to data processing. However, in real-world production environments, data is generated continuously, and failing to process that flow immediately leads to latency, bottlenecks, and consistency issues. Having personally dealt with real-time recommendations, state synchronization, and event delay problems in high-traffic environments, I’ve often asked myself, "Is batch processing really the right approach for this?" This course begins with that very question. It explores how to use Apache Flink to perform computations the moment data flows, manage state securely, and produce accurate results based on Event Time—all from a practical perspective. Beyond simple theoretical explanations, you will experience how real-time stream processing systems are designed and operated through actual source code and architectures. For those who found real-time processing vague or were curious about the world beyond messaging, this course will provide a clear sense of direction.

When you're doing backend development, at some point you face this dilemma. As services grow and traffic increases, there comes a moment when simple REST communication and CRUD structures feel limiting. I experienced the same problem in real-world work and went through many trials and errors between performance and structural complexity. The solution I chose in that process was NATS. Its simple configuration based on a single binary, ultra-low latency performance in microseconds, and the fact that it provides just the right amount of essential features for real work—from Pub/Sub to Queue Groups and JetStream—made it a very practical choice in actual service environments. This course is not about listing NATS features. Based on the problems I faced in real work, I explain with code and flow diagrams which situations led me to choose NATS, why, and how I designed the architecture. This is a course designed to help everyone—from those new to messaging systems, to backend developers preparing for jobs, to senior developers contemplating better architectures—understand distributed systems and grow to the next level.

Learn how to design and process large-scale data architecture that handles hundreds of billions of data records using only pure SQL and MySQL's core features, together with a Toss developer who handles hundreds of billions of financial traffic transactions and a developer who started as a non-major and is now developing platforms in Pangyo.

This course covers RPC communication techniques that maximize performance in large-scale MSA (Microservice Architecture) environments. Going beyond simple gRPC practice, you'll learn how to implement stable and efficient inter-service communication in real production environments where hundreds of microservices operate simultaneously. Based on Golang, the course covers Protocol Buffers (proto) syntax writing, automatic code generation and service implementation, gRPC structure and advantages over existing RPC, and performance optimization strategies with a practical focus. To ensure easy understanding for non-majors and server development beginners, the course provides step-by-step explanations from RPC concepts to gRPC's internal operating principles, enabling you to develop practical skills that can be immediately applied to real services.

How do you handle exploding traffic? Learn how to build resilient and flexibly scalable architectures through practical design patterns based on EDA (Event-Driven Architecture) using Kafka, Spring, CDC, and Temporal. Explained clearly and simply with real-world experience from a Kakao developer, making it accessible even for non-majors. A hands-on, practical course covering real-time data flow, event processing, and microservice integration all at once!

Develop a scalable order processing system with real-time event streaming capabilities using Spring Boot 3.x + Kotlin to build a Kafka cluster, leveraging PostgreSQL CDC, Debezium Connect, and Apache Avro schema.

In this course, rather than directly covering theory, you will learn how to effectively use Redis in code through hands-on practice.

This course covers how to set up multi-module projects from scratch using Kotlin and Spring Boot. It proceeds with a hands-on approach, covering everything from the basic concepts of modularization to Gradle configuration, managing dependencies between modules, and actual application development. If you are a beginner or intermediate developer looking to learn the fundamentals and practical application of multi-modules, please refer to this course.

Learn the process of building essential Observability in a Microservices Architecture (MSA) environment from basics to practical application. Master standardized data collection using OpenTelemetry, trace storage and search through Grafana Tempo, and visualization using TraceQL through step-by-step hands-on practice. You can learn how to track service flows through distributed tracing, identify bottlenecks, and analyze the root causes of failures.

Learn the process of building data pipelines using Apache Airflow from basics to practical application. Understand Airflow's core concepts and architecture, and master advanced design patterns frequently used in practice such as dynamic DAGs, parallel processing, distributed processing, and Custom Operators through hands-on exercises. Set up a practice environment with Python and Docker, and develop practical skills to design and operate real workflows.

This course explores microservice architecture and distributed environments not as a simple list of technologies, but from a 'design perspective' required in actual work and interviews. Starting from the differences between monolithic and MSA, it progressively covers incremental migration strategies, modular monoliths, clean architecture and hexagonal architecture, clearly explaining why each choice is necessary and the trade-offs involved. Through hands-on practice, you can directly verify the intent of the structure and learn about core issues inevitably encountered in distributed environments—such as data consistency, transactions, inter-service communication, and failure handling—through realistic scenarios. Based on actual questions and perspectives from Kakao interviewers, this course aims to go beyond simple knowledge acquisition and elevate your way of thinking about distributed systems to the next level.

Using Spring Boot 3.x + Kotlin, we build a 3-instance cluster, and utilizing Redis Pub/Sub distributed messaging and an Nginx load balancer, develop a scalable WebSocket real-time chat server capable of handling large-scale traffic.

This course is a master class that systematically covers the fundamental principles and practical applications of MongoDB. Starting with core MongoDB concepts, you will systematically learn essential topics for practical work, such as database design, CRUD operations, indexing, aggregation pipelines, performance optimization, transactions, and security. It explains topics step-by-step so even beginners can understand, and you can deeply learn the working principles of MongoDB through exercises and examples. This is the best introductory and practical course for developers who want to build strong MongoDB skills for practical work.

This course is a master class that teaches Kotlin's 🌺 Coroutine, covering everything from theoretical foundations to practical application in a standard manner. It systematically covers core principles and structure, the necessity of asynchronous programming, Coroutine builders and scopes, exception handling, channels, Flow, and other key features frequently used in practice, step by step. Each concept is explained with hands-on examples, making it easy for beginners to understand and immediately apply them. This is the best introductory and practical course for developers who want to build strong Coroutine skills for real-world use.

Let's build a project using Ktor, the most popular project in Kotlin, and master Kotlin! 😆

Kotlin mastery via virtual payment server course.

I am covering the know-how on how I studied and got a job, starting as a non-major.

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.

You can learn about JWT and ws communication using Spring Boot, and how to handle high TPS.

Learn the process of building essential Observability in a Microservices Architecture (MSA) environment from basics to practical application. Master standardized data collection using OpenTelemetry, trace storage and search through Grafana Tempo, and visualization using TraceQL through step-by-step hands-on practice. You can learn how to track service flows through distributed tracing, identify bottlenecks, and analyze the root causes of failures.

This course covers RPC communication techniques that maximize performance in large-scale MSA (Microservice Architecture) environments. Going beyond simple gRPC practice, you'll learn how to implement stable and efficient inter-service communication in real production environments where hundreds of microservices operate simultaneously. Based on Golang, the course covers Protocol Buffers (proto) syntax writing, automatic code generation and service implementation, gRPC structure and advantages over existing RPC, and performance optimization strategies with a practical focus. To ensure easy understanding for non-majors and server development beginners, the course provides step-by-step explanations from RPC concepts to gRPC's internal operating principles, enabling you to develop practical skills that can be immediately applied to real services.

Let's improve performance by utilizing the basic technology stack! After the improvement, we will check the changes through load testing and monitoring tools! We will also prepare for interviews on each topic!

A Java advanced project course for beginner developers who want to develop practical skills! We'll build a console-based kiosk ordering system together using Spring Core, JdbcClient, and H2 DB.

When you're doing backend development, at some point you face this dilemma. As services grow and traffic increases, there comes a moment when simple REST communication and CRUD structures feel limiting. I experienced the same problem in real-world work and went through many trials and errors between performance and structural complexity. The solution I chose in that process was NATS. Its simple configuration based on a single binary, ultra-low latency performance in microseconds, and the fact that it provides just the right amount of essential features for real work—from Pub/Sub to Queue Groups and JetStream—made it a very practical choice in actual service environments. This course is not about listing NATS features. Based on the problems I faced in real work, I explain with code and flow diagrams which situations led me to choose NATS, why, and how I designed the architecture. This is a course designed to help everyone—from those new to messaging systems, to backend developers preparing for jobs, to senior developers contemplating better architectures—understand distributed systems and grow to the next level.

OODP's 25 patterns teach various methods for object-oriented software design.

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

This course will help students understand Java classes in more detail and use them more naturally. This will lead to more object-oriented programming.

Knowing design patterns will make it easier to learn not only Spring but also many other technologies and programming languages. It will also help you develop more flexible and reusable object-oriented software.

AI is no longer a choice, but a matter of survival. Reduce development that took 3 days to 30 minutes, delegate repetitive tasks to AI, and focus on solving more important problems. With AI-native development methods that you can apply immediately in real work, not just theory, we'll show you the definitive way to be recognized as a "developer who's good at AI" at your company.

Based on an understanding of Reflection and Annotations, it helps you clearly understand how the Spring framework operates!

Are you curious about whether what you learned in school will work in practice? The purpose of this lecture is to guide you on how to use the skills you learned in theory in practice.

<25 English Technical Interview Questions and Answers by Local Australian Java Developers> is for all those who want to work as Java language programmers. Since Java language is a computer language that is constantly in demand worldwide, this lecture will be a useful guide for preparing for actual interviews not only for those who want to work overseas but also for those who want to work domestically.

This course prepares you for the Information Processing Engineer practical exam solely through solving past exam questions. Instead of unnecessary theory or extensive content, it's designed to lead directly to 'passing' by focusing on past questions that repeatedly appear on actual exams. It reflects the latest exam trends, allowing you to quickly grasp key points and question patterns, and you can learn answer-writing techniques through the problem-solving process. This is a course optimized for test-takers aiming to pass efficiently in a short time.

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.

Currently, Android can be developed using the Java and Kotlin languages. The same Android application can be developed using either language. This course covers most of the content from basic to advanced Android application development, and all code is written using the Kotlin language starting from the basic content. We also use Material 3, Google's latest UI library. This course mainly covers menus, Android application components, threads, and Fragments among the entire Android curriculum, and future courses are planned to cover more in-depth topics. Soft Campus will always strive to provide the latest lectures. Thank you.

This course provides an in-depth study of multithreading and concurrency, from basic principles to practical applications.

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

"The Era of Coding with AI: A New Productivity Paradigm for Java Developers" This course is a practical Cursor AI utilization guide for Java developers. Beyond simply copying AI-generated code, you'll learn Vibe Coding methods that maximize development efficiency through collaboration with AI. By leveraging Cursor's powerful code understanding, refactoring, and documentation features, you'll master AI coding workflows step by step that can be immediately applied to real-world projects. In an era where AI writes code for us, "developers who can effectively work with AI" now have the competitive edge. Start your upgraded development experience as a Java developer with this course.

Kevin's Easy-to-Understand Java Developer (Web Developer) Roadmap Story