My two cents

[Martin Nowak]

On Monday, 23 October 2017 at 11:02:41 UTC, Martin Nowak wrote:
> In C++ incremental rebuilds are simple as you compile each file 
> individually anyhow, but that's the crux for why C++ 
> compilations are so slow in the first place.
> Compiling multiple modules at once provides lots of speedups as 
> you do not have to reparse and analyze common/mutual imports, 
> but on the downside it cannot be parallelized that well.

dub supports --buildMode=singleFile --parallel to mimic that, but 
it's very wasteful.

For example gtk-d took way over a minute with single file 
compilation, but only a few seconds when being compiled at once