[4] Martin formed Jonathan Fire*Eater with high school friends Paul Maroon, Stewart Lupton, Matt Barrick, and Tom Frank from Washington, DC.

On stage Martin played organ, piano, and bass guitar but his main contributions to the Walkmen were as composer, arranger, and lyricist.

[5] It was met with critical acclaim from Pitchfork,[6] NPR's All Things Considered,[7] USA Today,[8] and The New York Times who called it, "An album of joyful children’s music that is also sophisticated enough for grown-ups to appreciate.

"[17] During a surprise performance at NPR Music's Tiny Desk Concert in December 2017,[18] Martin announced his fourth solo album Reminisce Bar & Grill.

It was dedicated to his late Jonathan Fire*Eater bandmate Stewart Lupton who died in 2018 of suicide after years of battling addiction, depression, and schizophrenia.

"[3] Vogue Magazine raved "The World at Night might just be his masterpiece"[21] while All Music said, "The album radiates so much care, empathy, and genuine emotion, listeners can’t help but be touched by it.

At its best, The World at Night evokes the strangest part of mourning: when your eyes fill with tears but they catch the light, making everything look brighter anyway.

"[23] Martin wrote and performed the original song, "Do-Dilly-Do (A Friend Like You)" for Laika Studios' Missing Link, The Golden Globes’ 2020 WINNER for Best Animated Feature.

[24] He co-wrote and performed on the song "Walking on a String" alongside Phoebe Bridgers and the National's Matt Berninger for Zach Galifianakis' Netflix film Between Two Ferns.

[25] His song "Let the Tall Ships Sail," from his 2020 album Green Beans and Tangerines was featured in season two, episode two of the Netflix original series Hilda.