The car keeps a diary
A Tesla generates an absurd amount of data about itself — and by default, all of it evaporates into the app’s ten-second attention span. The oldest running service in our home lab exists to catch it: TeslaMate, the open-source logger, quietly journaling the car since January.
The stack
Four small services on the home server, running so long they qualify as furniture: TeslaMate itself, which talks to the car; a database that keeps the history; a dashboard tool that graphs it; and a messenger that tells our home-automation system what the car is doing at all times. Plugged in? Charge level? Just arrived? The house knows, and the automations get to care.
What a year of car diary tells you
The dashboards turn vibes into numbers:
- Every drive, with energy used and efficiency — which is how you actually learn what highway speed, A/C, and Florida summer do to range, instead of arguing with the range estimate.
- Every charging session and what it delivered — home charging habits, visualized honestly.
- Phantom drain, finally measured. A parked car spends energy; the diary shows exactly how much and blames the right features.
- Battery health over time — the long, slow degradation curve, tracked calmly across the year instead of panicked about in forums.
When we changed cars this year, the pattern held: point TeslaMate at the new one and the diary just continues.
Why self-host it at all
Because this is the house philosophy applied to the driveway: the data is ours, it lives here, and it accumulates value the longer it runs. A year of driving history in your own database is a fundamentally different asset than a mobile app’s current-month view — and it cost nothing but a few containers on hardware that was already humming.