The Pirate's Hymnal is a new collection of sea shanties adding 29 shanties and rules for them to the world of the Dark Caribbean. It also has a brand new class in The Shanty Man who can make use of these songs in new and interesting ways. The class is available for free on the Jolly Rogenerator.
This is a companion discussion topic for the original entry at https://rpg-trader.com/products/6178/the-pirate-s-hymnal