He has worked as a solo electronic musician and as a remixer for bands and singers such as Charlotte Gainsbourg, Daft Punk, Beastie Boys, Bloc Party, and Nero.

Also that year, as well producing numerous remixes and releasing his Walkman 2 EP, Sebastian joined Kavinsky to open with DJ sets for Daft Punk on their Alive 2007 tour.

The soundtrack contains also "L'enfance d'un chien" performed by Sébastien Tellier, which features on his first album L'incroyable Vérité, released in 2001.

Later, his debut album Total was announced, followed by the release of a video for the title track featuring a series of violent and sexual images.

That year also saw the release of The EP Collection, a box set of vinyl Total singles along with tracks "Organia" and previously unreleased "Holloback".

[9] The same year, he composed, produced and arranged the track "Stabat Mater", performed by Woodkid, which features on his album, The Golden Age.

In 2014, Sebastian composed and produced the title track "American Beauty/American Psycho" for the band Fall Out Boy on their album of the same name.

In 2015, Ed Banger owner Pedro Winter announced that Sebastian had finished producing a few songs for Frank Ocean, allowing him to work on his next album.

[11] Sebastian appears on the track "Facebook Story" and has also participated as an instrumentalist on "White Ferrari" and "Godspeed" on Frank Ocean's album, Blonde, released in 2016.

Gainsbourg received a Victoire de la Musique in the "Female Artist of the Year" category in 2018 for Rest.

Sebastian created the soundtrack for the Yves Saint Laurent Winter 18 Collection campaign, which was held on 27 February 2018 in Paris, France.

[15][16] The same year, he co-composed the soundtrack for the film The World Is Yours (original title: Le Monde est à toi), directed by Romain Gavras, starring Karim Leklou, Isabelle Adjani and Vincent Cassel.

[19] The album released on 8 November 2019 by Ed Banger Records, with, among others, Charlotte Gainsbourg, Sparks, Sevdaliza and Syd as guests.