I was thinking about using boost::iostreams in place of my own 'array stream', but was surprised by the poor performance. When doing RPC calls, I often use the following pattern: a) calculate buffer space required to serialize arguments b) allocate buffer space c) serialize into buffer I use a stream type with an interface of write(),read(), putc(), getc() etc similar to iostreams. In doing some basic tests serializing a struct I get the following numbers: stringstream: 2.4e6 times/sec stream<array_sink>: 3.2e6 times/sec stream<null_sink>: 1.5e6 times/sec mystream<char*>: 8.7e6 times/sec (fixed size array) mystream<size_t>: 1.07e7 times/sec (similar to null_sink, but tracks bytes written) Perhaps this is the difference between polymorphic and static method calls? In any case, there is no reason for stream<null_sink> to take twice as long as array_sink as there are no memory copies, all write should be no-ops. It would probably be useful to add a size_sink that can be used to track the number of bytes written and thus avoid dynamically resizing buffers.