Here is one you might even be able to deliver this week. :)
Make it possible to sort practice exercises by difficulty level.
And a slightly more complicated one.
Make it possible to filter practice exercises by concept. I want to be able to find practice exercises to reinforce the concept that I have just learned if I am not 100% confident after the learning exercise.
The difficulty sorting/filtering is genius. I do get annoyed about that every time I start a track especially since an exercise’s difficulty can change per track. I have to scroll the track exercise list to see what’s on the easy level.
+1 from me. I was just about to post the same feature request.
Is it planned to add these features?
@W8CYE Can you clarify what you are missing exactly?
If I look at the Go track, on the “Overview” tab and on the “Exercises” tab, in both cases exercises are sorted by difficulty. Which track are you looking at where this is not the case? (This can be fixed by changing the config.json of the track.)
Also practice exercises for a concept should be shown in syllabus tab on the box for the concept.
Not many tracks have this configured yet but you can see it in Elixir and Python. It is a lot of work to define the concepts for a practice exercise so that’s why it is still rare but all tracks with a syllabus have open GitHub issues about this.
This would be amazing! Take a look at the Java track, for example, there are medium and hard exercises listed before easy ones:
It’s annoying to always scroll to the bottom to look for the easy exercises.
I just recently understood, that the exercises are listed in the order of the config.json file. So until now I just added new exercises to the end of the respective list. That is why the C++ track has new exercises popping up at the very end.
The difficulty rating is an ongoing debate, but I am planning to sort them in the same way as the python track - by difficulty and then by context.
Note, Glenn has a jq script to help sort the exercises by a criteria 
I’ve done this for Pyret and Vim script. I sort by binned difficulty (1-3 for easy, 4-6 for medium, and 7-10 for hard) and then by exercise name. If you sort by slug, pop-count / Eliud’s Eggs will be out of order.
