After some digging, I realized that this was due to protobuf , was updated and that mosh hard-coded to use protobuf 2.4.1 .
So, all I had to do was return from protobuf 2.5.0 to 2.4.1 . On a homegrown Mac, this is done using the following steps:
> brew versions protobuf 2.5.0 git checkout 019364d /usr/local/Library/Formula/protobuf.rb 2.4.1 git checkout 544209f /usr/local/Library/Formula/protobuf.rb > git checkout 544209f /usr/local/Library/Formula/protobuf.rb > brew unlink protobuf > brew link protobuf
source share