Pattern: Recursive Self-Improvement Is Already Operational — 70-90% of Next-Model Code Written by Claude, Spotify Ships 650 Agent PRs/Month

r/ClaudeAI / Anthropic·high signal

Anthropic researchers confirm 70-90% of code for next-generation models is now written by Claude. Spotify's fleet management tool Honk merges 650+ agent-generated PRs into production monthly, with senior engineers not writing code directly since December 2025. Anthropic built Cowork (its knowledge-worker productivity tool) in 1.5 weeks using Claude Code, spending more time on product decisions than writing code. Release cycle compression from 6-12 months to weeks is the most visible evidence.