Cherny: Anthropic built its Cowork AI agent in 10 days using Claude
Boris Cherny · Head of Claude Code: What happens after coding is solved | Boris Cherny · Feb 19, 2026 · at 53:16
Boris Cherny, Head of Claude Code at Anthropic, discusses how Anthropic rapidly developed and deployed Cowork using its own AI coding agent.
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“And so over 10 days, they just completely used quad code to build it. And, you know, co-workers actually, there's this very sophisticated security system that's built in, and essentially these guardrails to make sure that the model kind of does the right thing, it doesn't go off the rails. So for example, we ship an entire virtual machine with it. And QuadCode just wrote all of this code. So we just had to think about, all right, how do we make this a little bit safer, a little more self-guided for people that are not engineers. It was fully implemented with QuadCode. Took about 10 days.”
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