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Onboarding to an unfamiliar codebase

The slowest part of joining a team is not learning the language — it's learning this codebase: what the pieces are, how they fit, and where the logic you care about lives. Understand turns that from an oral-tradition process into a self-serve one. A new engineer can explore the real structure directly instead of interrupting the people who already understand it.

This page is a suggested ramp-up path; each step links to its full how-to.

Day one: get oriented

Start with the 10-minute tour, then lean on:

  • Information Browser — right-click anything to see what it is, what it calls, and what calls it. This is the single most useful habit for a newcomer.
  • Browse Mode — click through the code like hyperlinks to follow a path without memorizing file names.
  • Find things fast — jump straight to a function, class, or symbol by name when someone mentions it in a standup.
  • Home dashboard — a project-level summary of size, complexity, and hotspots; a quick answer to "what kind of codebase is this?"

See how it fits together

Read the map before the streets:

Trace real logic

When you need to understand how a specific routine behaves, reason through its control flow with the Virtual Debugger — no need to build or run the system first.

Keep what you learn

Onboarding is also note-taking. Capture your findings where the next hire will see them:

Ask the codebase questions directly

Understand's AI chat answers questions grounded in the project's real cross-references, which is a fast way for a newcomer to ask "where is X handled?" without pinging a teammate. See Chat with the AI about your code and Why Understand with AI.

For the team lead

Onboarding onto legacy or safety-critical systems has its own concerns — see Understanding & reverse-engineering legacy code and Safety-critical software.