Jannit Maarten is the boatbuilder of the Castle and an extremely hard-working and self-sufficient woman.
Jannit didn't think of herself much as a girl. When she was fourteen, she dressed herself as a boy and ran off to sea. She lived on a farm when she was younger, and she "hated cows, loathed pigs, and disliked chickens."
Taking on apprentices
Nicko Heap and Rupert Gringe are apprenticed to her. After Nicko gets trapped back in time, she has to release his Apprenticeship and goes to Sarah Heap to get the Release signed. She was sad about the Release, and Rupert realized that Nicko helped out a lot around the Boatyard. He, too, missed Nicko very much, and wished he would return.