Whenever I automate a circuit, my two favorite modules are the Shelly 1 UL and the Shelly 2.5 UL. They’re my go-to for 90% of the circuits I work with, because they’re so quick and versatile, but offer great functionality. Here’s a quick install of a Shelly 1 with a Decora style switch in a standard single gang box.
Under cabinet lighting with the Shelly RGBW2 is a fantastic smart home project for nearly anyone. The RGBW2 is low voltage, requiring a 12v or 24v power source, can support up to four channels (Red, Green, Blue, and White or four White channels), and offers the same ability to enjoy local and cloud control of the device as other Shelly relays. What’s more, if you don’t want a permanent installation, you don’t even need to use a single screw to mount the project.