Claude Code now runs daily maintenance on Anthropic’s software with a 46 percent merge rate
Published: August 14, 2026 — THE DECODER (Matthias Bastian)
Anthropic is testing whether Claude Code can handle daily maintenance of the company’s own software. In a few weeks, the AI created 388 pull requests, and 180 were merged after human review.
Claude has been running daily maintenance on Anthropic’s in-house apps for “the last few weeks,” according to Boris Cherny, the Anthropic engineer who created Claude Code. Instead of tying up developers with repetitive maintenance work, Claude handles it on its own. Cherny calls the results “surprisingly positive.”
In his post, Cherny describes a setup where Claude, via Tag, runs daily routines through a dedicated Slack channel called “proj-claude-maintains-apps” across all of Anthropic’s platforms: iOS, Android, desktop, web, CLI, and the Agent SDK.
Twelve routines cover the full range of code upkeep
Claude runs specialized maintenance routines including:
| Routine | Function |
|---|---|
| Crash Fuzzer | Finds real app crashes and generates fixes for the root causes |
| Ant-only Shipper | Delivers or removes forgotten internal features |
| Logic Simplifier | Simplifies nested business logic |
| Logic Bug Fixer | Models complex logic to find and fix errors |
| Dup Unifier | Merges duplicate implementations |
| Dead Code Removal | Removes code that is proven to be unreachable |
| Useless Test Pruner | Removes tests that can never fail |
| Shipped-Feature Inliner | Removes feature flags for features that have been fully released |
| Flaky-Test Fixer | Analyzes and fixes unstable CI tests |
| Abstraction Improver | Simplifies overengineered abstractions |
| Abstraction Police | Fixes layer violations in the architecture |
Cherny shared prompts in Slack with plain-language instructions (e.g., start daily crash fuzzing on iOS/Android/desktop using real apps without mocks, trigger crashes, create PRs with fixes).
388 pull requests created, just under half merged
Claude created 388 pull requests across Anthropic’s repositories in the first few weeks. After automated Claude Code review and human review, 180 were merged (~46%).
Claude usually gets PRs right on the first try. When it doesn’t, the team tweaks the routine so the AI does better the next day. Anthropic is looking at ways to speed up the merge process for mechanical changes.
Cherny describes the experiment as “early signs of life” that autonomous AI-powered app maintenance could work.