Polish session musician, double bass player and bass guitarist. Best known for the band Poluzjanci. He collaborated with the leading Polish stars of popular music (e.g. Urszula, Natalia Kukulska, Edyta Górniak, Justyna Steczkowska, Kayah) and jazz (e.g. Dorota Miśkiewicz, Anna Serafińska, Marcin Nowakowski) as well as with many foreign artists. In 2006 Żaczek released his first solo album, Mutru. In 2009 he released his second album - Balboo.