Hi, D newbie here,
The library is on par with Google Protobuf performance-wise and does not need a pre-compiler like Protobuf does, but instead uses the meta programming facilities of D to (de)serialise D data types from/to binary messages. Some samples and unit tests are included.
Here's the code if anyone wants to have a look: https://github.com/sinisa-susnjar/msgbuf
(I am sure there is a lot of room for improvement)