The Challenge category was something I suggested way back. Initially, it was supposed to be about the challenges of translating C macros to Zig. I posted a couple problems/puzzles but then just went out of ideas.
Right now, I’m trying to get a community documentation effort for Zig off the ground. One definite need is better code examples. Since the Challenge category exists already I was thinking maybe we can reuse it for this purpose. For instance, someone brought up in another thread the builtin @popCount. I sort of know what it does but I have zero clue why we would use it. Example code that would illustrate how it would be used in real-life would be immensely useful.
This should be far more sustainable than before. Creating a new challenge would simply be a matter of copy-and-pasting “Provide a useful example for X”. And the result is going to be useful for the whole Zig community.
I think what you propose is already a valid way to use the challenge category, initially it was about translation, but we already broadened that because it seemed too narrow.
The main thing about challenges is that the initial description should provide a clear definition for what is an acceptable answer for that challenge.
Here is the description of the challenge category, I think it fits what you describe: