How to read Moby(Docker) source code systematically

So far I can use Docker skillfully, but still do not understand the internal implementation details and task execution workflows.

Moby is a huge project with lots of files and millions of lines of code. I have no idea where to start reading. And I don’t know how to read such a large amount of code efficiently and understand the logic inside clearly.

Background Info: I can use Docker command skillfully. And I haven’t find any resources to explain Moby source code in detail. I am basically familiar with Golang.

Source: StackOverflow