I've been working on https://github.com/foonathan/type_safe for the past 20 months or so. What started as an experimenting ground for type safe programming facilities quickly turned into a general mix bag of utilities. However, it became my most popular project, so there is something in there people find really useful. And with that multiple approached me wanting to have it added to Boost, so here I am. I do realize that not all of it is suited for Boost: some of it has overlap with existing libraries (e.g. optional/variant), some of it has better implementations elsewhere (e.g. improved integer types) and some of it is to novel/experimental (e.g. stuff like constrained_type). But there are some things that could be useful for Boost. I'm mainly thinking of the strong typedef facility. I plan on splitting the library up into multiple parts anyway (see also https://github.com/foonathan/type_safe/issues/82), so please let me know whether there is anything you'd like to see being prepared for Boost. Thanks, Jonathan