Claude Code

How Was CC Built? ClaudeCode Founding Engineer Reveals: 90% of Code Written by Claude, “Agent for Agents” Built in 3 Days, Developers Still in Demand

Claude Code

How Was CC Built? ClaudeCode Founding Engineer Reveals: 90% of Code Written by Claude, “Agent for Agents” Built in 3 Days, Developers Still in Demand

# Listening to the Rain — Claude Code's AI-First Journey **2025-10-13 12:55 Beijing** --- ## Introduction Claude Code began as a small command-line tool for listening to music. Today, it has **become a storm in the developer community**. ![image](https://blog.aitoearn.ai/content/images/2025/10/img_001-114.jpg)

By Honghao Wang