[sixthDot]

D standard library uses much templates. So only what's used or what is not templatized get linked in the binary. The runtime somewhat tries to follows this too, aka the "pay-as-you-go" strategy as it is called in the dlang world.

For small applications this works even if certain templates can easily lead to have half of the standard library pulled in (e.g a few conversion, a few format, a few regex and boom, the size explodes).

A subset of the language called betterC allows to fully get rid of the "base", but requires to write much more code to get things done. Maybe this is why prakis managed to get the smaller binary ? The comment is not very clear about the methodology...