So, before I can begin designing this device, I must have a concept and some design criteria ready.

• It must not be over-ruled by the light-switch (i.e. most lighting hacks will only work whilst the light power switch is in the up position, I want this to work more like a 2-way switch)
• Integrate almost seamlessly with the switch face-plate so that a normal 2-way switch is still possible
• Have IoT functionality (i.e. can be controlled and automated using Node-RED)
• Can be used like a normal light switch (can be used as 2-way switch, etc.)

Like I mentioned above, once installed, it should interact (at least electrically and physically) like a normal light switch. Normal light switches are usually SPDT and as such have three contacts; Common, 1-way and 2-way. Forgive me and/or correct me if I'm getting any of this wrong as I have very limited experience with these things as I am not an electrical engineer by profession, merely a hobbyist.