It's worse than that, I think. They had some code that expects input in a certain format, they wanted it to accept input in a variety of other formats, and category theory was apparently necessary to come up with the idea of a format converter from each new format to the original format. Extremely basic. Trying to pretend it's a CT application is just pretentious in the extreme.
As far as I can tell, this is what category theory is for. It lets you take some quite basic structure or piece of work, and describe it in rigorous, impressive-sounding terms.
