His first instrument, based on the sape and selodang (traditional instruments from Kalimantan), was built in 2018 and was called MU74n (mutant). The concept behind it arose from the “haze season” in Kalimantan, a result of the increase in forest fires over the last 10 years. Arminandi's intent with MU74n is for it to become a voice of contemporary Kalimantan.

Since May 2019, in addition to building instruments, he has been involved in interdisciplinary project Manangkata, which explores experimental music. He is also a member of Pontianak's Balaan Tumaan Ensemble, a musical community which explores and researches musical traditions from Kalimantan Barat (West Kalimantan) province. He is now focused on composing and building new instruments.