Ask HN: best approach to writing a Windows service?

I need to write a native app that runs on recent flavors of Windows which can talk to a hosted API service and make changes to the local PC. It's a very simple set of tasks that need to be completed, but I'm at a loss for where to start. The last time I compiled something for Windows was using Visual Basic 6 and Windows XP -- things have changed since then. Any pointers are welcome!