config/local/ — this machine only (gitignored)

Everything in this directory except this README is gitignored: it belongs to one machine / one physical vehicle and must never be committed or shared through trunk (RFC #380 §1, §3).

config/local/
├── calibration/<serial>/    # per-UNIT intrinsics/extrinsics (SN-0042/, ...)
└── overrides.yaml           # (future) 4th precedence layer, below CLI flags

Calibration overlays (vehicle units)

A vehicle type (config/vehicles/<name>/) is shared and committed; a vehicle unit is one serial number whose calibration drifts and gets re-measured in the field. A fleet entry's unit: SN-0042 binds config/local/calibration/SN-0042/, and tools/fleet/resolve_fleet.py exports it to the robot container as CALIBRATION_DIR (/root/AirStack/config/local/calibration/SN-0042). Recalibrating writes here — never into the shared vehicle package.

No enforced file layout yet: put the camera intrinsics / extrinsics files your drivers consume in the unit directory and point the driver config at $CALIBRATION_DIR. CALIBRATION_DIR is empty when the fleet entry declares no unit:.