05 of 10
Infrastructure
Smart Parking System.
A camera-driven parking system handling 100,000+ vehicles across a 6-story garage with a 75-camera installation. Zero double-bookings since launch, after a database unique constraint replaced application-layer concurrency checks.
- Built at
- DevTechGuru
- Scale
- 100,000+ cars, one 6-story garage.
- Category
- Infrastructure
- Booking Errors
- 0
- Cars Tracked
- 100k+
Context
Security guards were recording licence plates by hand. Queues formed at the gate and revenue was leaking.
Challenge
Sync live camera feeds and payment state in real time, without latency drivers would notice.
Non-negotiables
- No double-bookings
- Video and database always consistent
- Every payment accounted for
Calls I made
- 01
Unique constraint on reservation
A unique database constraint on the reservation table catches a duplicate booking at insert time, so the same spot can never be sold twice.
- 02
Hardware adapter layer
A pluggable adapter abstracts camera vendors. Hardware swaps do not change application code.
Trade-offs accepted
- Under heavy load the system refuses a booking rather than risk a conflict. Conservative on throughput, zero double-bookings.
- Deferred analytics dashboards until the reservation path was stable.
Outcome
100,000+ vehicle transactions since launch, zero double-bookings recorded.
When software drives a physical action, partial correctness is not enough. The cost of a wrong answer is on the ground.
Stack
- Django
- Electron
- SQLite
- JavaScript
- Node.js
- Camera adapter layer
Django
SQLite
JavaScriptGot something similar in mind?
Send 3 lines. I reply within a day.