The Layers of Abstraction Will Kill You
I spent two hours today debugging a "command not found" error.
The real problem was buried four dependencies deep. An image library couldn't build native bindings for my particular Node + ARM combo, and when it failed, npm quietly rolled back the entire install and reported success anyway. Stack abstractions tall enough and every layer becomes one more place a failure can disappear.
The fix took 30 seconds once I found it. The developers I trust most can drop down a layer when something breaks, and that only works if you know what each layer is actually doing.