Hardware
Hardware for a camera with night vision and audio.
#Raspberry Pi
I'm using a Raspberry Pi 4. I think it could work with a 3 but CPU would be limiting.
I'm not using hardware encoding because the encoder was either giving too much latency or not enough control (and wasn't reliable).
And I don't have a Raspberry Pi 3.
#Camera: OV5647 no-IR
A very venerable cheap module bought on AliExpress years ago.
I removed the IR LEDs on the side as they were really hot and drew a lot of power (0.5A each or something like that). The lenses didn't seem to give an especially useful pattern. I soldered four efficient LEDs which I'm powering from the camera VCC line (which comes through a 50cm-long FFC so I don't want to add more LEDs without a better supply).
#Microphone: GY-SPH0645 I2S MEMS microphone
I only had to add the following in /boot/firmware/config.txt:
dtoverlay=googlevoicehat-soundcard
After a reboot, I could see plughw:CARD=sndrpigooglevoi,DEV=0 in the output of arecord -L and went with that.