I am currently setting up a Spigot 1.12 server and i want to use PermissionsEx, but what can i use the best?

Is there a 1.x build compatible with 1.12 and the best choice?
Or can i better use a 2.x build compatible with 1.12?

And is PermissionsEx 2.x still compatible with Vault?
Or can i better replace calls from my own plugins to Vault with calls to an API from PermissionsEx 2.x?

Since this ticket contains programming topics, you'll have to wait for @zml2008 to reply.

And, for what it's worth, PEX 1.23.4 works on Minecraft 1.12, according to the servers I've talked to lately.

PEX 2.x is still in development— no official releases yet —so I haven't used it at all and can't answer anything about it. As you can see on our tickets page, there are a lot of tickets for PEX 2.x and SQL issues that I can't answer. Those all need zml to reply as he's the only one around with experience in both. (And he's very busy, most of the time.)

Okay, thanks for the info. Then i will use pex 1.x for now.

As a further note, Vault is and will always be the preferred API for working with PEX on Bukkit/Spigot -- PEX is generally not guaranteed to have a stable API, especially with the 2.0 release not finalized. However, we maintain our own Vault hooks in 2.x so those will remain compatible.

Thanks @zml2008 for that note.