dlang.org makefile pains

[Jakob Ovrum via Digitalmars-d]

I used to contribute to dlang.org now and then before the 
makefile revamp. Now every time I try, I end up fighting with the 
makefile.

> make -f posix.mak apidocs-serve
> LATEST=2.070.2 <-- place in the command line to skip network 
> traffic
> *starts downloading crap from downloads.dlang.org that I 
> already have*

Alright, let's try that again.

> make -f posix.mak apidocs-serve LATEST=2.070.2
> *still downloads crap I already have*
> *Phobos build errors because latest Phobos isn't compatible 
> with DMD 2.069.2*

How do I make it use ../dmd and ../phobos? I've looked at 
CONTRIBUTING.md and the Wiki and I don't see this explained 
anywhere.

All I want to do is test DDox with local dlang.org changes and 
local Phobos changes.