If you want to say/convey you are working on a book/paper, what is the correct way of saying so other than plainly saying I'm writing a book?
I noticed 'under writing' has a specific meaning and cannot be applied here. I also thought about, under composition (composing?) but I'm not sure if that's the correct term.
I'm writing an email to a possible colleague, and I want to sound formal and not too generic. that's why I'm asking this.
By the way, if it's not clear, from where I got the idea for under+ing, it came from 'under construction'.