I've just read that filmicFilmic is not completely implemented: https://developer.blender.org/D2659.
Notes:
- The results appear to be identical to the original Filmic config, but I left out some parts like the renaming of color spaces, BT.1886, grayscale and new roles. Some of those things might be worth adding as well if they are backwards compatible.
...
Q: Are there significant differences between filmicFilmic shipped with blenderBlender and its repository? Before going down the rabbit hole: What does that mean to us and what version is preferedpreferred?