Accellum
An IoT operations platform that turns MQTT card and gateway signals into device health, checkpoints, access history, and live dashboards.
Project introduction
Accellum is an IoT access and attendance operations platform. Bluetooth cards and gateway devices publish signals that are translated into device status, checkpoints, movement, and auditable access history.
What I worked on
- Built MQTT ingestion for device alive, gateway status, and checkpoint topics
- Implemented WebSocket-driven dashboard updates alongside durable PostgreSQL records
- Developed user, card, device, building, access-log, and role-permission workflows
- Added validated Excel import/export for operational data
- Supported TypeORM migrations, Docker services, Mosquitto, and MinIO-compatible storage
Architecture
NestJS subscribers validate MQTT payloads, resolve device and card identities, persist normalized records through TypeORM, and broadcast relevant updates over Socket.IO. The Nuxt/Vuetify admin provides role-aware monitoring and management while historical records remain searchable and exportable.
Outcome
The system turns low-level device traffic into a dashboard administrators can monitor and audit. Portfolio captures use fictional data and expose no real individual, facility, or access-event records.
How a card detection becomes attendance data
The card only broadcasts its identity. The gateway turns that radio observation into an application event; the backend then validates, interprets, stores, and publishes the result to operators.
Two detection modes, two session strategies
Monitor mode models presence from repeated signals and checks out on timeout. Checkpoint mode models an entry/exit session with a five-second debounce and explicit room-transfer handling.