If you subscribe to descriptive linguistics at all (which you must if you believe languages can naturally change) a quick google search reveals that performant is actually very much an adjective (i.e. it is commonly used as one to the point that one would be considered obtuse to refuse to recognize it as such).

To be fair one can also find a fair number of discussions about whether performant is a word in that google search, so "performant as an adjective" is clearly a newish use of the word.

Edit: after reading your reference I can comment that journal/book editors mostly do not subscribe to descriptive linguistics and it is probably good that they do not (to not take chances with parts of language that might turn out to be fads).

There are plenty of published journals going back decades that accept performant as a term of art.

Your edit is a good pont. The prescriptive/descriptive dichotomy always seems a bit odd.

If you are a linguist: i.e a social scientist who job it is to explain how languages work in this world. Then you must describe.

If you are a language teacher then your job is to prescribe. And you make a good point that journal editors have good reasons to do the same. (Especially when looking after authors from STEM fields!)

> Performant is not an adjective, it is a noun. "One who performs".

It has been used as a noun, but rarely. You are thinking of the -ant formation seen in informant: one who informs. But this is not the only -ant in English, and it is not the one used here.

That which is resistant, resists well; it offers a good amount of resistance. Those who are insistent, insist strongly; they make plenty of insistence. That which is compliant, complies fully; it is very much in compliance.

That which is performant, performs well; it offers (a) good performance.

As to what good performance is:

> Software can perform well at its job (not crash, get the correct answer) but may not perform efficiently (takes a long time, has unbounded resource use, uses a brute force pattern).

This is a reasonable objection—I agree with it, wanting speech to be plain—but here is something to oppose it: I suspect that just about everyone who clicked on this article, including the two of us, knew precisely what the author wanted the word to mean, even if they had an objection to that use of the word. Performant has sprung to life, and it describes an efficient performance.

As for what I think of the word: the English language is already rich with others which would do just as well, which is probably why this one seems so jargony. It is one of those technical words that sounds more like a social signal—"I know what I'm talking about"—than something precise: "This is what I'm talking about."

Unless it's being used an an adjective, in which case it's an adjective.

Poor xkcd. Frowning upon people freely interchanging their, they're and there is not being grammar police (unlike complaining about split infinitives, dangling preposition etc). It seems such people that make this mistake are too lazy and arrogant to correct themselves and are too eager to call names. The placard ruined what would have been an average comic..

This is in fact not a discussion about the semantics of performant.

It was made into one.

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.

I wonder which words were not made up. The true name of God?

Fight the real enemy, like the word "learnings"