Hello, I realize that Boost doesn't promise ABI compatibility across releases, nor even API compatibility according to the FAQ: How can the Boost libraries be used successfully for important projects? Many of the Boost libraries are actively maintained and improved, so **backward compatibility with prior version isn't always possible**. Deal with this by freezing the version of the Boost libraries used by your project. Only upgrade at points in your project's life cycle where a bit of change will not cause problems. Individual bug fixes can always be obtained from the boost repository. (emphasis mine) OK, but *in practice* is there a large amount of work adapting existing client code to a new release? I'm asking in order to gauge whether it is useful for a linux distribution (Debian) to keep multiple versions of Boost available simultaneously; e.g. 1.34.1 and 1.35. Currently Debian provides only the latest version of Boost. Thanks, -Steve