Once installed, you edit a config.js file to add your preferred modules, such as local OpenWeatherMap data. Other "Mirror" Projects
A two-way mirror , a monitor (with its casing removed), a Raspberry Pi, and a wooden frame. Project: Mirror Free Download
The software is free to download and community-supported. How to Get Started Once installed, you edit a config
If you aren't looking for a DIY smart mirror, you might be referring to: a monitor (with its casing removed)
To build your own, you will typically need to download and install the software via a terminal on a Raspberry Pi.