A method and system for automatically updating a self-learning data repository. The method is executed in a processor of a server computing device to store a fingerprint map of an area in the self-learning data repository, the fingerprint map having positioning fingerprint data that includes magnetic spatial derivative fingerprint data, receive, at the self-learning data repository, at least one of mobile device signal data and mobile device sensor data correlated with a sequence of positions along a trajectory describing a movement of a mobile device relative to the area, the sensor data including mobile device magnetic spatial derivative data, and automatically update, using the processor, the self-learning data repository by adding the at least one of mobile device signal data and mobile device sensor data to the positioning fingerprint data.