An augmented reality musical instrument & tool that encodes stones, pavement, and infrastructure with sound and music. The instrument conceals your smartphone as it detects patterns in the street using computer vision. Those patterns act as triggers for musical experiences. Users can explore the city as they look for triggers left behind by street composers. This turns a familiar city into an infinitely programmable musical environment waiting to be explored. This project was inspired by going to the beach as a kid and watching a man with a metal detector scan the sand looking for treasure.