What techniques actually help you get better at reading unfamiliar codebases?

Team experience helps too. After working with the same people for a while, you start to recognize their design habits and assumptions. Consistent naming, formatting, architecture, and useful comments reduce the effort required to understand unfamiliar sections. When the logic is genuinely complicated, sketching it out or walking through it with a teammate can save a lot of time.

The skill is closely tied to writing code yourself. Understanding how programs are structured, tested, debugged, and changed gives you useful expectations when you encounter someone else’s implementation.

The teaching part has helped me as well. Explaining a small section out loud forces me to identify what I know, what I’m assuming, and what I still need to investigate.

Treat the code like something you’re reverse-engineering. Take a small library or application you actually care about, find a feature you use, and trace how it works. Set breakpoints, step through the execution, inspect the call stack, and—if useful—make a small change or deliberately break something to see what depends on it.

Explaining a file or function aloud is useful for the same reason: teaching forces you to turn vague impressions into a concrete model. Drawing the control flow on paper and writing short notes or comments can also expose gaps in your understanding.

Learn the common shapes of the technology you’re using. For example, a typical web framework may put request handlers in controllers, business logic in services, and database access in repositories. A frontend project may be organized around pages, components, and state management. Those conventions give you a working hypothesis about where to look, even when each project differs slightly.

Then use a concrete entry point, such as an endpoint, visible bug, or small feature, and trace the calls from there. Editor navigation, definition lookup, full-project search, documentation hovers, debuggers, stack traces, and runtime tools make this much easier. Reading code is less about staring at files in order and more about following a path through the system.

A big part of it is simply repeated exposure. The more codebases you study, the more familiar patterns you recognize, and the faster you can orient yourself in the next one. Don’t start by trying to understand the entire project. Pick one function, file, data structure, bug, or feature and follow it piece by piece. It’s completely normal for the bigger picture to be unclear at first; the connections become visible as you collect smaller pieces.

Start with baby steps and accept that you won’t understand every line immediately. Follow one function line by line, or start with a key data structure and track where it is initialized, changed, passed around, and cleaned up. Code is nonlinear, so you usually need to assemble the mental model gradually rather than read it like a book.

Simpler projects can be good practice, especially small command-line tools or libraries with a clear purpose. Once you’ve built confidence with those, larger systems become less intimidating.