Trying to do the same on OSX Yosemite
DMD64 D Compiler v2.066.1
DUB version 0.9.22, built on Sep 22 2014
: dub --build-mode=singleFile
Target vibe-d 0.7.21 is up to date. Use --force to rebuild.
Building motherbrain ~master configuration "application", build type debug.
Compiling using dmd...
Compiling source/app.d...
Compiling diet template 'index.dt'...
Compiling ../../../../../../../../.dub/packages/vibe-d-0.7.21/source/vibe/appmain.d...
Linking...
ld: library not found for -levent
clang: error: linker command failed with exit code 1 (use -v to see invocation)
--- errorlevel 1
FAIL .dub/build/application-debug-posix.osx-x8664-dmd2066-D4654FFE7804D10ED72DFB2B25337E5C/ motherbrain executable
Error executing command run: dmd failed with exit code 1.
Is there any resolution for this yet?