The idea of the microkernel OS architecture is more that 50 years old and the term itself is just a few years younger. Over the years, it has been implemented in countless variants and modifications, it has served as a basis for intriguing OS experiments, it has gained strong position in the mission-critical and safety-critical areas and while it is still not the dominant architecture in the general-purpose desktop OS domain, it has had major influence on the "mainstream" operating systems as well.

This talk, however, is not about the history. Instead, we describe where are the microkernel-based operating systems today, who works on them and why, who uses them in production and why, where they aim for the future. The purpose of this talk is also to present the basic practical experiences with the existing microkernel-based operating systems — not to compare them, but to provide the potential users and contributors with an initial sorted list of operating systems they should look into in more detail depending on their needs.