The platform engineering team at Anthropic has transitioned to using Claude for all code generation tasks. According to team lead Katelyn Lesse, engineers now focus primarily on system design, verification, and ensuring code quality, while the AI handles the actual implementation and maintenance.
During a migration of a large codebase from Python to Rust, the team utilized AI agents to manage development, monitoring, and verification. The company has already implemented autonomous test repairs by AI agents and is currently exploring workflows that allow agents to modify the codebase directly.
Data from June 2026 indicates that Claude generated over 80% of the code merged into the company's production repositories as of May 2026. This shift in development practices has impacted the company's internal structure and hiring strategy.
Between early 2025 and 2026, the proportion of junior staff in the technical department decreased from 21% to 14%. Additionally, the share of junior technical roles in new hiring dropped from 27% to 9%, as the company now prioritizes candidates with higher levels of autonomy and judgment.
