Another IT guy, some 25 years of experience. I work most of the time as IT consultant (developer, architect, team lead) on different platforms and with different technologies (I don't really see a point in being a specialist, however this might seem strange to most recruiters).

When using UNIX'oids, it's most often Linux and when using Linux it's most often Ubuntu. Other than that I feel comfortable with Windows as development platform and I'm falling more and more in love with Apple stuff. I'm quite happy with these three platforms and switch back and forth whenever the one I am using is getting on my nerves for one reason or another.

On the development side, I like C# as a language a bit more than Java, Maven and Java-Frameworks much more than Nuget and the like. It's quite some time since I developed something natively for UNIX/Linux, simply because it's rarely requested by my customers. I keep doing some script development and system administration tasks to keep my own IT infrastructure alive and to see what's new.