Piotr Kaliński, known as Hatti Vatti, is a Gdańsk-based electronic music producer, guitarist and DJ. His work develops between dub, ambient, IDM, UK bass music and improvisation, combining electronic production with the sound of acoustic instruments. Kaliński is also involved in the projects Hinode Tapes, Nanook of the North and JANKA, and runs the experimental label Kanu Kanu Recordings.

In 2024, the Belgian label R&S Records released Zeit, an album recorded with saxophonist Piotr Chęcki, bassist Paweł Stachowiak and drummer Rafał Dutkiewicz. The material combines dub, synth-based ambient, kosmische musik, psychedelia, contemporary jazz and echoes of Japanese electronic music. Hatti Vatti became the first Polish project to be released in the R&S Records catalogue.