I don’t know. I found it yesterday by a chance; was looking for Invistra, but couldn’t remember the name; searched on “Common Lisp format library” and that one popped up too. Took like just few minutes to understand it and adapt it, so that is where I see the value.

The biggest problem with it seems to be it does not support string escapes, like a new line; at least not for me; perhaps I don’t understand it yet; will look at that later.

I also have no idea how it compares performance-wise with real printf via FFI; I am not sure if that really matters though.