VecByteBuf is currently the C++ implementation of ::MongoExtensionByteBuf from the C API. The prefix Vec comes from using std::vector<> to hold the bytes. The naming can be a bit misleading since it means ByteBuf implemented as a vector rather than a vector of ByteBufs. Furthermore, the class is defined inside of byte_buf.h and we don't have any other ByteBuf class. We should be safe to rename VecByteBuf to ByteBuf and VecByteBufHandle to ByteBufHandle since we don't foresee adding a different implementation of ByteBuf in C++ which would then require some differentiation (cc will.buerger@mongodb.com). Finally, this would make us stick to our naming convention of having MongoExtensionFoo in the API and Foo as the implementation with FooHandle/FooAdapter as the connectors.