The composer of the score for the 2023 film Poor Things, his debut solo album, Winterreise, was released in 2020.

He attended Adams' Grammar School in Newport and graduated from Cambridge University with a degree in classical music.

[2] In 2018, Fendrix wrote the "appropriately abrasive"[3] score for a performance of the play Ubu Roi by Alfred Jarry at the Victoria and Albert Museum.

[4] In December 2018, he collaborated with Black Midi on the song "Ice Cream", which appeared on a charity Christmas compilation, created by Brixton musicians.

[7] Director Yorgos Lanthimos commissioned Fendrix to write the score for his film Poor Things after hearing Winterreise.