Jeff Morhous shares a framework for using AI tools to accelerate onboarding to new codebases

Jeffrey Morhous, Senior Software Engineer at CoverMyMeds, outlines a four-step approach to onboarding into unfamiliar codebases using AI coding tools like Claude Code, Cursor, and Codex: initial app understanding, mapping architecture, identifying tests, and setting up local execution.

The framework aims to build a compact mental model through documentation, component diagrams, test strategy, and a runnable local setup—compressing initial exploration into a structured map of architecture, entry points, key flows, boundaries, and test strategy.

Morhous advises using an Opus model (a more capable reasoning-heavy model) when running the `/init` command, noting that tokens spent on reasoning up-front are well-spent, because cheaper models like Sonnet are more likely to overlook critical architecture or contain consequential mistakes in planning.