I've recently been working with Performance Co-Pilot (PCP) - specifically, creating some PCP add-ons (known as PMDAs) for exposing custom application metrics to PCP.
While doing so, it became pretty clear to me, that although PCP's PMDA C API is very efficient, a good quality C++ wrapper could significantly cut PMDA development and maintenance time (for people like me, at least), while also increasing runtime safety by building-in all of the checks and balances that most PMDAs (should) perform, in a generic reusable manner.
This sounded like a bit of fun, and suited my present hunger for some more advanced C++ API design work, so went about implementing such a library.