Callstack describes agent-led legacy codebase migrations methodology

The author outlines a structured, brownfield-first methodology for executing large-scale codebase migrations using an autonomous agentic framework. By combining business case justification, a software-factory model with modular agent roles, rigorous telemetry monitoring, and canary rollouts with hard-stop criteria, engineering teams can minimize risks and avoid the pitfalls of full rewrites. The approach emphasizes starting with low-risk leaf flows and capping autonomous feedback loops to ensure stability. Open article →