Automatic feeders fail in boring ways: kibble jams, bowls overflow, cats pry open lids, and Wi-Fi outages break schedules. A reliable DIY feeder uses an auger screw, a load cell under the bowl and a local real-time clock so feeding does not depend on the cloud.
The auger is better than a flap for dry food because it dispenses predictable portions and resists cat tampering. The load cell verifies how much actually landed in the bowl. If the motor turns but weight does not increase, the firmware flags a jam and retries gently.
Keep the food path easy to clean and avoid printed surfaces touching food unless you seal them or use a removable food-safe liner. The electronics should be isolated from dust because kibble crumbs get everywhere.