Shelly Dimmer Gen4 - Built-in multiprotocol dimmer Wi-Fi 6, Zigbee, Matter, neutral-free, 200 W

The Dimmer Gen4 is a bit like the Swiss Army knife of in-wall dimmers. You slip it behind an existing switch, with or without neutral, and transform standard lighting into a controllable source adjustable down to the percentage. The real novelty compared to Gen3 is the multiprotocol built into a 38 mm enclosure: Wi-Fi 6, Bluetooth 5.0, Zigbee and Matter. For a renovation where the neutral is missing in the electrical box, it's exactly the kind of module that unlocks a room without touching the wall.

With Home Assistant, that's where the module really makes sense, but you need to understand one thing. Native Shelly integration, via Wi-Fi and 100% local, remains the gold standard: it exposes everything, fine dimming, mJS scripting, MQTT, webhooks, HTTP API, and even power consumption measurement when you have the neutral. On Matter, it works well and stays local. The word of caution is Zigbee: the Gen4's Zigbee firmware is still young, and several users report that in ZHA you lose some dimming control and input configuration capabilities. Also worth noting is that Matter and Zigbee are mutually exclusive; the module starts in Matter by default and you need to manually switch the firmware to move to Zigbee. In short, if the goal is HA, you go through native Wi-Fi integration, period.

You have to be honest about the trade-offs. Without neutral, you lose power consumption measurement and some electrical protections, and you need to add a Shelly bypass for loads under 20 W. The dimming range also depends heavily on the LED bulb used, with recalibration required each time you change the load, which is standard for this type of dimmer. Up against a Fibaro Dimmer 2 in Z-Wave, more expensive and locked into a single protocol, the Shelly is simply unbeatable on the openness-to-price ratio, around 45 euros.

In the end, you have an open, local, multiprotocol and affordable dimmer that checks just about all the boxes for a serious Home Assistant setup. You only drop half a point for the improvable Zigbee firmware and the limitations inherent to neutral-free operation. That gives a solid 4.5/5, and for a dimming module at this price, it's clearly a safe bet.