Build time

[JG]

Hi,

The program I writing is around 3000 loc and recently I noticed a 
large slow down in compile time which after investigation seemed 
to be caused by my computer running out of memory. The compile 
was using more than 15GB memory. I tried using lowmem and that 
did solve the memory problem but the compile still takes around 1 
minute. Any suggestion on how to try and improve the build time. 
I am currently using dub.

Of course one could try to use fewer templates and less meta 
programming but that seems to defeat the purpose of using d.