Maybe it's good to mention that a home automation system (Home assistant, Domoticz and Openhab) is optional, as long as the device has access to a MQTT broker. I don't use a home automation system, but I have a Rasperry Pi with a MQTT broker running. I wrote my own software that listens to the MQTT topic to which the Modernizr publishes a message. Works great for simple tasks, like sending a push notifications on doorbell press.
I set up the doorbell to work with HomeKit via Node-Red, and it works perfectly. My only issue is with the power supply: the product description says it's a 3.5mm barrel connector, but it's actually 5.5mm. Aside from correcting the description, I'd suggest swapping it out for USB. The power required is 5v, and even though 5.5mm barrel connectors are common, they are rarely used with 5v power supplies - they're much more commonly some multiple of 3. So it is unlikely a user will just have one lying around (vs. about ten chargers I had with the right connector but wrong voltage). Since USB is 5v, and has become the standard connector for small devices, it would be much more convenient to just use that (but preferably USB-C for robustness and future-proofing).
I ordered this board to automate my doorbell and I really like the quality of the board. At first, Erik sent me the wrong board and left me a message. So I returned the board and got the right one a day later. Fast shipping, great build quality and good communication with the seller!
Erik is a great guy! Fast shipping of the product, all well packaged in anti-static bags. Everything was well documented and I could easily solder it together. Because of my lack of knowledge I have asked Erik for help and he has helped me further. I am very happy! Great guy, great product! Thanks!