With DMD, vibe.d and DUB at master, I get the following build warnings when running ./build.sh to build DUB, and everything stops:
Running dmd...
source/dub/installation.d(34): Warning: const field with initializer should be static, gshared, or an enum
source/dub/internal/vibecompat/core/file.d(93): Warning: explicit element-wise assignment templ[16LU..dollar - 1LU] = (suffix)[] is better than templ[16LU..__dollar - 1LU] = suffix