This is just a little note to point out that the game didn't have achievements when it launched, but they've now been added. The store page hasn't been updated yet to mention achievements under game features. If you don't own the game yet, you can see the available achievements at
https://www.gog.com/u/YOUR USERNAME/game/1833504782

Yeah, they are added, but they are not working. None of the achievements are unlocking for me.

According to the global stats, 5 achievements have been unlocked by someone, so they don't appear to be completely broken. For now I only have the game on my wishlist, so I don't know what could be wrong firsthand.

You can try posting in the List of broken GOG Achievements thread and see if someone there has any helpful tips. The thread also tracks games that lack achievements that are available on Steam, so Vesper has been brought up before.