The Google Home Mini (1st-gen), launched in 2017, is a compact smart speaker that originally relied on Google Assistant to handle voice queries, timers, music, and more. However, many users prefer to avoid sending their voice data to Google for privacy reasons or want to integrate the device into a local smart home ecosystem. An open-hardware drop-in board now makes it possible to repurpose this speaker into a Home Assistant-compatible device. Below are answers to common questions about this modification.

What is the Google Home Mini and why would you want to modify it?

The Google Home Mini is a small, affordable smart speaker that primarily uses Google's cloud-based Assistant to respond to voice commands. While convenient, it sends audio recordings to Google servers, raising privacy concerns for some users. By modifying the device, you can bypass Google's cloud and run a local assistant like Home Assistant, keeping your voice data on your own network. This also allows for custom automations and integration with a wider range of smart home devices.

What is the $85 drop-in board and how does it work?

The drop-in board is a custom-designed open-source circuit board that replaces the original logic board inside a 1st-gen Google Home Mini. It maintains the speaker's audio components but swaps the proprietary Google Assistant hardware for a module that can run Home Assistant's voice interface. Priced at $85, it includes a microcontroller, Wi-Fi connectivity, and necessary drivers to interact with the speaker's original microphone and speaker array.

How does the board replace Google Assistant with Home Assistant?

Once installed, the board acts as the new brain of the speaker. It runs a lightweight version of Home Assistant, a popular open-source home automation platform. Instead of sending voice data to Google's cloud, the board processes commands locally or through a user-defined server. You can configure it to respond to wake words, execute automations, or control smart devices via MQTT, REST APIs, or other protocols. The modification effectively turns the Google Home Mini into a private, offline-capable smart speaker.

Who is this board intended for?

This board is aimed at tech enthusiasts, privacy-conscious users, and DIY smart home hobbyists. It's ideal for people who already use Home Assistant and want to repurpose existing hardware rather than buying a new device. Basic soldering skills and comfort with opening electronics are required, as the installation involves desoldering the original board and soldering in the replacement. Users should have experience with Home Assistant configuration to fully utilize the board's capabilities.

What are the benefits of using Home Assistant on a Google Home Mini?

Using Home Assistant instead of Google's cloud gives you full control over your data and voice interactions. You can set up custom wake words, integrate with local smart home hubs, and create complex automations without relying on an internet connection. The speaker remains functional as a voice-controlled device, but all processing stays within your home network. This reduces latency, enhances privacy, and allows for features like speech-to-text using local models such as faster-whisper or vosk.

Is the board easy to install? What tools are needed?

Installation requires intermediate soldering skills. You'll need a soldering iron, solder, a screwdriver set, and possibly a multimeter for testing. The process involves disassembling the Google Home Mini, carefully removing the original circuit board (which is glued in place), and soldering the new board's connectors to the existing microphone and speaker pins. Detailed instructions are provided by the board's creator. Expect the job to take 1–2 hours for someone experienced with electronics.

Where can you get the board and is it considered open hardware?

The board is sold through the developer's website or platforms like Tindie or GitHub. It is indeed open hardware—schematics, PCB layout files, and firmware source code are publicly available under permissive licenses. This allows anyone to inspect, modify, or even produce their own version of the board, fostering a community of developers and privacy advocates.

Does the modified Google Home Mini still work as a smart speaker?

Yes, after modification the device functions as a fully voice-controlled smart speaker but now runs Home Assistant. You can ask for weather updates, control lights, play music from local sources or streaming services (if configured), and set timers—all without any data leaving your home network. The speaker's original audio quality remains unchanged. However, features like multi-room audio and deep integration with Google services are lost, replaced by the flexibility of an open ecosystem.