Enables N-acylsphingosine amidohydrolase activity. Involved in regulation of water loss via skin; sebaceous gland development; and sphingosine biosynthetic process. Acts upstream of or within ceramide catabolic process and regulation of lipid metabolic process. Located in endoplasmic reticulum. Orthologous to human ACER1 (alkaline ceramidase 1). [provided by Alliance of Genome Resources, Apr 2022]