[bionsuba]

People on embedded systems use a custom runtime, and people who want to avoid the GC use the compiler to disallow GC usage in their entire program by using the @nogc annotation.

There are other less extreme solutions, such as the ability to have some threads be registered with the GC and others not. Also, you can just find your bottle-necks and mark those specific functions as @nogc. Some people also turn off automatic collections and manually trigger them only when it's ok to pause.