Anthropic engineer Boris Cherny, creator of Claude Code, revealed that the AI tool took over daily maintenance tasks on the company's internal applications. In a few weeks, the system created 388 pull requests and 180 were merged after human review, a rate of about 46%.
Automated routines
Cherny said Claude runs 12 specialized routines through a dedicated Slack channel called “proj-claude-maintains-apps” across all Anthropic platforms: iOS, Android, desktop, web, CLI, and Agent SDK. He described the results as “surprisingly positive.”
Among the routines are Crash Fuzzer, which generates fixes for faults found in simulators; Dup Unifier, which proposes merging duplicate implementations; and Dead-Code Remover, which eliminates unreachable code. The instructions are given in natural language, without elaborate prompt engineering.
Results and adjustments
The review combined automated analysis by Claude Code with human review. Cherny said Claude usually gets it right on the first attempt; when it does not, the team adjusts the routine to improve the next day. The engineer described the experiment as “first signs of life” that autonomous AI app maintenance can work.
Anthropic is now looking for ways to speed up the merging of mechanical changes of this kind.
