D-Programming-Language/phobos — comment on commit 9c2f390be07927ef08a9d681924afcb90892b3cb
File:  line 0
By eco:

I don't really understand the error:

unittest
Error: 'unittest' not found

But you do need the DLLs in the curl binary download to be somewhere in the path. I've opted to place them in the bin directory along with dmd as that is going to most likely be in the path for windows users but you can place them wherever you feel most appropriate (Windows\System32 would work, for instance).