Cartography: Solving Software Development Scaling

Hi I'm starting a dev tool company and trying to solve the problem of scaling software development. In other words I'm looking for a way to keep complex code-bases understandable.

Software development in the beginning is always super quick. As the app balloons in size, and more devs join, you end up spending more and more time just reading code, making sure you understand what's going on.

Looking to talk to some people to see what their processes and pain points are!