Safety notice

Read this before you build anything from this project.

• Mains electricity can kill or start a fire. The in-wall build connects to 220 V or 120 V. Only a qualified electrician should do any mains work, with the circuit switched off at the breaker and checked dead with a tester.
• These designs are uncertified. No lab has tested them, and they carry no approval mark (CE, UL, SEC or any other). They may not meet the electrical rules where you live.
• These designs are unproven. Some have never been built. Each guide shows its status. Expect mistakes, and report them.
• I am not an electrical engineer. This is a hobby project, designed with AI assistance and checked with design-rule tools, not by a qualified engineer.
• Rules differ by country. Wire colors, earthing, box sizes, and who may legally do electrical work all vary. In some countries only a licensed electrician may change fixed wiring. Never identify a wire by its color; test it.
• Insurance. Installing an uncertified device in your home's wiring may affect your home insurance or your compliance with local building rules. Check before you install.
• Low-voltage builds have risks too. Batteries, USB power and soldering can cause burns or damage. Never connect any pin to anything that is or was connected to mains.
• You build and install at your own risk. The designs, firmware and instructions are provided “as is”, without warranty of any kind, as their licenses say.

If you are unsure about any step, stop and ask a qualified electrician.