All words are "imprecise" and "made-up". My understanding is that performant is totally legal French, meaning efficient or effective, with usage dating back at

All words are "imprecise" and "made-up". My understanding is that performant is totally legal French, meaning efficient or effective, with usage dating back at least 4 decades. If you're not into stealing random words from other languages, I have to question why you're into English in the first place.