In late 2020, lead actor Leng Heng Prak passed away during the film's post-production process. 'Karmalink' is dedicated to his memory.
Director Jake Wachtel cast lead actors Leng Heng Prak and Srey Leak Chhith from his filmmaking course for children living in disadvantaged areas of Phnom Penh, Cambodia, part of the Filmmakers Without Borders initiative. They were his favourite students and had both grown up in Phnom Penh's Tralop Bek neighborhood, where the film is set.