As a developer, diving in a new code base is not uncommon: you've just been hired, you change of project, you want to help an open source project, the open source library your project depends on is buggy, etc. It's like entering in a underwater cave, you don't know the treasures or the monsters you'll find there, neither if the path is treacherous or if it's a true labyrinth where you'll get lost. You can prepare yourself, you can plan your visit, you can equip yourself, you can survive and find the gem you're looking for...
The gem trace_calls https://github.com/toch/trace_calls
The original snippet of code using TracePoint API https://gist.github.com/toch/82fd93ca449500d21f00