I Reduced a Week-Long Dev Task to 1 Hour with Claude Code

Introduction Recently, I tried out Claude Code on a development project. I'm writing this down as a memo of what I learned and my thoughts on it. What is Claude Code? Claude Code is an AI agent developed by Anthropic, specialized for code generation. The official documentation describes it as follows: Claude Code is an agentic coding tool that reads codebases, edits files, runs commands, and integrates with development tools. It's available in terminals, IDEs, desktop apps, and browsers. Claude Code is an AI-powered coding assistant that helps you build features, fix bugs, and automate development tasks. It can understand your entire codebase and work across multiple files and tools to complete tasks. In short, it's a tool that autonomously handles the full development workflow: reading code, implementing changes, running tests, and creating pull requests on GitHub. Background In my day-to-day work, I maintain and develop various systems — one of which is an ETL tool. This ETL tool con