The Grug Brained Developer (2022)

“Good debugger worth weight in shiny rocks, in fact also more”

I’ve spent time at small startups and on “elite” big tech teams, and I’m usually the only one on my team using a debugger. Almost everyone in the real world (at least in web tech) seems to do print statement debugging. I have tried and failed to get others interested in using my workflow.

I generally agree that it’s the best way to start understanding a system. Breaking on an interesting line of code during a test run and studying the call stack that got me there is infinitely easier than trying to run the code forwards in my head.

Young grugs: learning this skill is a minor superpower. Take the time to get it working on your codebase, if you can.

There was a good discussion on this topic years ago [0]. The top comment shares this quote from Brian Kernighan and Rob Pike, neither of whom I'd call a young grug:

> As personal choice, we tend not to use debuggers beyond getting a stack trace or the value of a variable or two. One reason is that it is easy to get lost in details of complicated data structures and control flow; we find stepping through a program less productive than thinking harder and adding output statements and self-checking code at critical places. Clicking over statements takes longer than scanning the output of judiciously-placed displays. It takes less time to decide where to put print statements than to single-step to the critical section of code, even assuming we know where that is. More important, debugging statements stay with the program; debugging sessions are transient.

I tend to agree with them on this. For almost all of the work that I do, this hypothesis-logs-exec loop gets me to the answer substantially faster. I'm not "trying to run the code forwards in my head". I already have a working model for the way that the code runs, I know what output I expect to see if the program is behaving according to that model, and I can usually quickly intuit what is actually happening based on the incorrect output from the prints.

[0] The unreasonable effectiveness of print debugging (349 points, 354 comments) April 2021 https://news.ycombinator.com/item?id=26925570

I wonder if Brian Kerninghan was using modern tooling or that comment was using quote from 70’s.

It's from The Practice of Programming, published 1999. Not a lot has changed in debuggers since then from what I can see.