I had a Voice Kit from Google's Maker Faire booth sitting around. I don't use voice assistants, but the kit has a Raspberry Pi Zero with a soundcard HAT, and a speaker and microphone all packed in to a pretty neat cardboard box. I figured I could build something using that to send and receive voice messages over Matrix - sort of a modern-day answering machine.
I'm running stock raspbian Raspberry Pi OS on the Pi in the box, so the first step was to get the speaker working. I made a summary of the instructions for this, following the guide to installing Google's AIY software on Raspbian.
See SETUP.md for how to setup and run the template project.
The basic structure of the project is the same as that of any other nio-template project.