60 FastAPI Lessons You Won’t Need to Look Up Again

The order is confirmed, but the notification is delayed. The response is faster, but if tasks disappear after a restart, where should you look first? Using real execution records from virtual orders, we’ll walk through RabbitMQ delivery and acknowledgments, deduplication, the Outbox pattern, retries, ordering, and backlogs. We’ll also establish a way to find and complete work that remains unfinished even after a fast response.

Why do requests wait when queries are fast? Locks. In a hands-on project using MySQL 8.0, Spring Boot, and JPA, reproduce record and gap locks, four types of deadlocks, long transactions and connection pool exhaustion, metadata locks during deployment, and lost updates with tests. Then fix them in code and verify the fixes with the same tests.

Learn NestJS in depth from the basics to professional level. Develop real-world projects using Prisma and Swagger, structured to provide a clear understanding of NestJS architecture and operating principles. After taking this course, you'll have the skills to confidently develop backend applications with NestJS.

Everything about Python asynchronous programming using FastAPI

Protect chatbots, RAG, and tool calls integrated with FastAPI from prompt injection, runaway costs, and privilege abuse. Defend them with dependencies, middleware, and tool code; verify your defenses with pytest and 50 security tests; and control releases with GitHub Actions gates. Complete 84 hands-on exercises with no API fees.

I have created an introductory CI/CD course that is easy to understand even for non-majors and can be applied immediately in practice!

Ahead of a major event, what should you prepare in your database, and what should you check first when it goes live? Practice your pre-, during, and post-event response sequence using training Aurora logs of Reader CPU spikes, lock waits, deadlocks, and failovers, along with diagnostic SQL.

Build a development pipeline with Claude Code’s headless mode, where a single-line issue comment triggers a PR ready for review. Codify team rules in CLAUDE.md, skills, and hooks, and add three human approval gates, a review bot, a false-positive ledger, and a cost cap.

This course covers the overall aspects of web servers required for game development, using the latest ASP.NET Core (Blazor, WebAPI).

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.

I build a DBA agent right on my laptop in Docker that measures MySQL and PostgreSQL every morning, creates a diagnostic report with A/B/C/N letter grades, analyzes problematic queries with EXPLAIN and drafts improvement requests, and reviews plans and costs for scaling connections and Readers up or down before a sale.

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.

After Kubernetes Basics: When Your Service Is Sick. Diagnose and fix issues by looking at symptoms like restarts, slowdowns, 502s, and stalled deployments, using only kubectl and metrics. Trigger eight failures yourself in a local Kubernetes environment on your laptop, then measure the before-and-after numbers under the same load.

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 series aimed at beginners, with the goal of developing web and app services to a level that can be genuinely commercialized, based on real-world experience developing actual web services. As the first step (part1-1), this course provides an in-depth explanation of intermediate Python for full-scale development, backend implementation with Flask [플라스크], and essential web technologies such as HTTP, REST API, and the MVC pattern.

Through this course, you can systematically learn core concepts such as Docker network basics, communication methods between containers, network configuration using Docker Compose, volume mounting and network sharing, and network settings using Dockerfiles.

Build an AI agent from scratch using Python and a single while loop, without any frameworks. In the introductory section, you’ll add tool design, failures and costs, memory, human approval, evaluation, and a web interface one by one to complete a small coding agent. In the hands-on section, you’ll implement RAG, multi-agent systems, and an MCP server yourself using real business reports from DART, then compare them numerically with LangChain and LangGraph.

Practice REST API and GraphQL while creating a simple SNS service based on React. We introduce how to easily and simply create a backend environment for frontend development.

This is a full-stack restaurant map tutorial that allows you to learn everything from front-end, back-end, Kakao Map API usage, and deployment all at once while creating a restaurant map of your favorite YouTuber.

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.