at will

Prepositional phrase

idiomatic

(idiomatic) at one's preference; as one sees fit

Japanese Meaning

好きなように / 意のままに / 任意に / 自由に

Guests may help themselves to snacks at will.

来客はお菓子を好きなだけ取って構いません。

Sense（1）

(idiomatic) at one's preference; as one sees fit

I'm writing my book at will - there's no deadline or minimum word count.