Anthropic engineer's farewell: built RL envs with Claude Code, zero lines hand-written
jxnlco · x · 2026-11-04
An Anthropic engineer (@catwu) announced her last day at Anthropic, and jxnlco called it a generational run. Two years ago, when Claude Code was a small internal tool, she had Claude build an RL environment — steering it for tens of hours without manually writing a line of code — which hooked her into joining the team. She recalls that at launch most users approved every permission prompt by hand and used Claude mainly for answering questions and writing tests, while today agentic workflows have transformed how the tool is used.
Related event: Claude Code early member Cat Wu announces departure from Anthropic(14 posts)→
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