Claude Code Helped Me Understand a Legacy Codebase in One Day

1 IgorGanapolsky 0 7/21/2025, 5:21:53 AM

I used Claude Code to onboard to a messy old React/Node repo, and it worked surprisingly well.

I asked it: - “Summarize this repo’s architecture” - “How is authentication implemented?” - “Which models are used in this folder?”

It gave me useful answers based on code structure and variable/function names. Saved me hours.

Bonus: This book helped me refactor what Claude exposed: [Working Effectively with Legacy Code](https://www.amazon.com/dp/0131177052?tag=igorganapolsk-20)

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Claude Code Helped Me Understand a Legacy Codebase in One Day

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