From the home page: "Vale is currently in alpha!" (https://vale.dev/)
(The inverse is "VC 1.0", which means pre-release but we had to meet a deadline, and "Programmer 1.0", which means it's the first stable version.)
I thought "Programmer 1.0" is more like +Infinity and never ever reached? ;)
Conventionally 1.0 is just the inflection point where things are featureful and stable enough that you start making guarantees about the stability of whatever interface/contract/API/whatever that matter to the consumer of whatever you are building.