This is a quick guide for how to set up an August Smart Lock Pro for use with Home Assistant using only locally hosted open source software.
This is a nice solution if you already have a deadbolt with a manual key-less toggle on the inside of the door since installation takes about two minutes and you don't loose the manual toggle capability even if the batteries die.
The initial setup process if full of badness (identity verification, cloud bullshit and location data) but after the one-time setup it will run locally with just z-wave and no proprietary or cloud stuff.
The August lock uses four AA batteries. They recommend non-rechargable batteries (probably due to the discharge curve for AA being better for correlating voltage with battery level and warning users about low battery before it's too late).
Note that you will need a bunch of non-free terrible software for the initial setup and to change certain settings. Specifically you will need an iOS or Android device with bluetooth, internet and in case