The manufacturing programming/test fixture is a fair bit of code running on a PJRC Teensy 3.5.  Over the last few weeks I have worked on various subsystems

1. Arduino library for the test fixture hardware itself
2. Silicon Labs C2 programmer for the Teensy
3. Hex File utilities
4. Simple display support for the cap touch control LCD screen
5. A custom test firmware to first program on the Charger's SI EFM8 micro-controller to allow detailed testing and calibration

And finally I have gotten them all stitched together along with a test sequencer and am writing test code.  It's tedious because for every test I have to figure out what's right and what the limits for valid measurements may be.  But I see the light at the end of the tunnel now.