To be able to build a zigbee unit that could fit in a standard wall box, I had to rebuild the triac unit using smd parts. I always thought that this technology was difficult for diy projects, but that proved to be wrong. Using solder past and a heat gun makes building a pcb with smd parts easy.
I designed the pcb, and had it fabricated in China. After sending the gerber files, it took only 7 working days to receive 10 2-layer prototype boards. I also ordered all components from China (which took a little longer). I did not use the zigbee controllers from Netvox, but ordered some cheaper parts which are also based on the TI CC2530 chip.
A connected light can be switched and dimmed locally by the 2 buttons and of course by issuing zigbee commands. A locally changed state will be reported to my home control program.
The cover is 3D printed.
Here are some pictures: