CRTP + compile-time introspection + static ctors = WIN

[Mathias LANG]

On Friday, 15 January 2021 at 18:31:18 UTC, H. S. Teoh wrote:
>
> And since static this() blocks are run at program startup and 
> dynamic
> library load time, this ensures that after program startup,
> `classLoaders` has knowledge of all types the program will ever 
> use.

Just don't use separate compilation or you're in for a lot of 
troubles.
https://issues.dlang.org/show_bug.cgi?id=20641