As a producer and songwriter, Halm has contributed to several notable projects, including two tracks on SZA's acclaimed album SOS, (Notice Me and Open Arms with Travis Scott,) Rosalía's hit singles "Con Altura" with J Balvin and "TKN" with Travis Scott (the former earning a Latin Grammy Award,) and "Evergreen (You Didn't Deserve Me at All)" by Omar Apollo.

[8][17] In 2019, he was named to Billboard's 21 Under 21 list of songwriters and producers, having co-written the Latin Grammy-winning[18] song "Con Altura" by Rosalia (featuring J Balvin) and co-writing and co-producing "Mood 4 Eva" by Beyoncé, Jay-Z and Childish Gambino, from the Grammy-nominated album The Lion King: The Gift.

[8] In 2021, "Mountains", performed by Charlotte Day Wilson and co-written by Halm, was sampled in the track "Fair Trade" by Drake featuring Travis Scott from the album Certified Lover Boy.

"[20] Omar Apollo's Evergreen (You Didn't Deserve Me at All) co-written and produced by Halm reached number 51 on Billboard Hot 100[21] after going viral on Tiktok.

[25] Halm co-wrote and produced two songs on the SZA album SOS, Notice Me and Open Arms (with Travis Scott).

[27] In September 2024 Rex Orange County released his long-awaited fifth studio album The Alexander Technique with six tracks co-written and produced by his friend Halm.