I just realised yesterday that the libs bundled with dmd (curl.lib in my case) doesn't have a win64 version bundled. Can you put a binary for that in lib64?
... although it new appears to be gone completely in that new bundle. Is that the new standard? Is there somewhere they should be sourced?
Can you also rename the libs in lib64/ to remove the '64' on the end? That's pretty annoying in build script to have different lib names.