[arccy]

prealpha is such a weird name, just call it a dev/nightly build or an actual alpha

[keyle]

Beta is typically close to feature complete.

Alpha is basically not close to feature complete.

Pre-alpha is check this out but here be dragons! For an OS it makes sense, seeing failure typically means a hard reboot.

[Lerc]

For the level of development I would consider preAlpha, I would count myself lucky if it built on any given night.

I think of it as, "hey, this one doesn't immediately implode. Let's let people look at it"