Concepts are finally coming! In this talk, we will go above and beyond to explore the full potential of this haunted by history feature. We will discuss how concepts may revolutionize the way the modern C++ code is written, including how concepts may provide better diagnostics and simplify the SFINAE altogether. We will also take a look at how to emulate concepts in the current standard and discuss the benefits of the design by introspection. Additionally, it will be presented how to write a loosely coupled, well-performing code by default and how to opt out to a dynamic dispatch using type erasure when necessary. Its final focus will be on increasing your testing productivity when applying the concepts driven design.