Jeroen Thesseling is a Dutch bassist and composer, renowned for his contributions to the progressive metal and jazz fusion genres. Born on December 23, 1970, he gained prominence as a member of the acclaimed progressive metal band Exivious, which is known for its intricate compositions and technical proficiency. Thesseling is also recognized for his work with the band Pestilence, particularly on their 2018 album "Hadeon," which showcases his virtuosic bass playing and innovative use of the fretless bass guitar. Thesseling's style is characterized by complex rhythms and melodic improvisation, often blending elements of metal with jazz influences. His work has significantly impacted the metal and fusion scenes, inspiring a new generation of bassists to explore the capabilities of the instrument beyond traditional boundaries. He has also collaborated with various artists, further solidifying his reputation as a versatile musician. In addition to his performance career, Thesseling is known for his educational contributions, offering insights and tutorials that emphasize technique and creativity in bass playing. His dedication to both performance and education continues to influence the evolution of modern bass music.