Here is the full list of all 37 Salt and Sanctuary achievements. It takes around 20-25 hours to unlock all of the achievements on Windows.
Achieve the maximum upgrade level of a weapon.
Defeat the Unspeakable Deep.
Take an oath to the Order of the Betrayer.
Take an oath to the gods of Fire and Sky.
Bear all possible brands.
Take an oath to The House of Splendor.
Discover your first brand.
Defeat the Kraekan Cyclops.
Take an oath to The Stone Roots.
Defeat the Mad Alchemist.
Take an oath to Devara's Light.
Defeat the Queen of Smiles.
Defeat the Sodden Knight.
Claim your first sanctuary.
Take an oath to The Three.
Aid a despondent thief.
Aid a questing knight.
Aid an unraveling sorceror.
Take an oath to The Iron Ones.
Achieve the maximum devotion level in your creed.