I have been running Pylenin.com on Hugo for the last 3 years. All my blogs use a category and tag taxonomy.
Although, I do want to move to Ghost, the unavailability of the category taxonomy is being a bummer.
Anyway, I can create a category taxonomy for my requirements?
Check if a Substring is Present in a Given String in Python
Escape sequences in Python String
Python String Formatting - The Definitive Guide 9. Common Python String Methods
The last article is a list of common Python String Methods. Each element in the list links to an article on one of the string methods.
Now there are more than 50 string methods. So I use a tag for them - python string methods. That way, the tag only shows the string methods articles and category page is not bombarded with all those articles.
You can visit this page to understand more about how the articles are structured.
It sounds like it’s all perfectly possible with the concepts in Ghost - we just don’t call anything “categories”. It sounds like you probably want to play with channels.