Designing Large-Scale Data Processing Patterns Based on Data Workflow Management with Toss Developers

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.

This course approaches 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 transition 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 not just at knowledge acquisition, but at elevating your way of thinking about distributed systems 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.

Learn SAGA transaction management techniques for maintaining data consistency in distributed environments through hands-on practice. Configure three microservices using Spring Boot and Docker, and implement both Orchestration and Choreography patterns with Kafka and MySQL. Through this course, you can master core concepts that are immediately applicable in real-world scenarios, including distributed transaction operation principles, compensating transaction design, and failure recovery handling.

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.

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

How to Handle Explosive Traffic Growth? Learn 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 Kakao developers, making it understandable even for non-majors. A hands-on focused course covering real-time data flow, event processing, and microservice integration all at once!

Kotlin mastery via virtual payment server course.

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.

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

Learn the essential process of building Observability in a microservices architecture (MSA) environment from basics to practical implementation. Through step-by-step hands-on practice, you'll master standardized data collection using OpenTelemetry, trace storage and search with Grafana Tempo, and visualization using TraceQL. You can learn the process of tracking service flows through distributed tracing, identifying bottlenecks, and analyzing 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.

This covers effective Redis usage, including precautions and applications, illustrated with examples from real-world practice or renowned historical cases.

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

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.

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.

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

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

You can learn how to send emails using AWS and Spring. Through this, you can study how to create an email verification system.

"Big Data + AI Full Stack Development" - The process of building big data that breathes life into AI is carried out in the form of a pilot project. We identify requirements, configure the platform step by step, and perform smart car data exploration and analysis.

This is a Kubernetes guide for beginners who don't know anything about Kubernetes. It is written in a way that even beginners can understand.

SQLD Yellow Book 176 Problem-Solving Course for those who studied but can't solve problems. After completion, you'll go beyond passing to become an expert. SQLD All-in-One Pass!

How is processing big data different from processing data with Pandas? Let's learn about Spark, an essential framework for big data processing.

This course explains how to perform data engineering, including real-time processing and external integration, which are the strengths of Logpresso. It also covers in depth how to assign reference data in real time, the precedence of logically related events, and CEP (Complex Event Processing) for detecting various actions and performing follow-up tasks based on collection intervals.

From Docker, Kubernetes to microservices, CI/CD, and service mesh, you can easily learn not only the basic theory but also the actual application implementation through examples. By organizing only the core contents necessary for actual use, it provides a starting point for learning about the element technologies covered in the lecture.

A new curriculum that incorporates the experiences of working developers using Docker, providing lectures that are different from existing textbooks and lectures. It starts from the fundamental question of why Docker should be used, rather than simple command usage.

Uncover true value in the age of data! 📊 Designing applications focused on data has now become essential. Develop the insight and skills your company wants with the latest trends and practical case studies. Start now with efficient data processing and design secrets! Your next step, leap into the data-driven world!

We will provide information on 3D spatial information data acquisition and mapping methods using drones, LiDAR, etc., and data visualization tools and techniques based on the application areas of 3D spatial information data, incorporating various case studies.

Redis is a fast and scalable open-source database. This technology is used to maximize performance in real-time applications, games, social media platforms, and more. However, to truly understand the power of Redis and use it effectively, you need a deep understanding. Now is your chance to learn Redis in a professional way. "Redis with Silicon Valley Engineers" covers a wide range of topics, from the core concepts of Redis to advanced features. This course is designed for everyone, from beginners who are new to Redis to advanced users.

This course covers how to use queries to build dashboards in Logpresso. We will discuss how to visualize real-time data, trigger alerts, and dynamically drill down and filter as needed.

This is a special lecture that can lay the theoretical foundation to simultaneously prepare for the Microsoft AZ-900 certification, and as the latest content reflecting the scope of questions as of May 2025, by providing content related to core data concepts, Azure's relational data, Azure's non-relational data, and Azure's analytical workloads in a form combining theory and practice, it can be utilized as a meaningful educational opportunity to not only obtain the certification but also take the first step towards becoming a data professional.

It covers basic data concepts, useful R functions and packages, and data analysis exercises, to allow anyone to perform big data analysis using R programming.

We introduce methods for planners and marketers without data analysis experience or technical skills to try data analysis at the most basic level, complete with various examples. Built on years of hands-on practice with over 2,000 participants in more than 100 companies and public institutions, the content is designed around the most practical analysis methods for data non-experts.

This course is designed to help you quickly learn server zero-downtime deployment methods using Nginx, Docker, and Spring Boot through hands-on practice. Learn Blue-Green deployment, which is frequently used in real-world scenarios, faster than anyone else!

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.

SSIS, SSAS, MachineLearning, BI, ETL. You can learn important technologies that cannot be found in domestic books, YouTube, lectures, blogs, and academies. I also recommend it to those who are interested in employment at domestic large companies, American large companies, and American state funding agencies.

Learn about Race Condition, a representative concurrency problem. Practice by comparing single server environments and distributed environments that cause concurrency issues. Understand transaction boundaries and isolation levels. Learn the differences between optimistic locking, pessimistic locking, and distributed locking.

In this lecture, you will learn how to create an ERD. You will learn database design. (The only big data design lecture in Korea)

You can quickly experience the process of deploying a sample e-commerce service to AWS and continuously improving it into a robust and efficient environment.