Case study 03
School Management Platform
Designed, built, and operated solo. A 1,000-student school runs on it daily.
Solo project: every model, endpoint, page, and deployment is mine, and I operate it in production.
Context
A private school in Gazipur ran admissions, attendance, fees, exams, and guardian communication on paper. I designed and built their entire platform solo, and still operate it: 23 data models, ~137 REST endpoints, JWT auth with per-route role middleware for seven user roles, running on Vercel and a DigitalOcean VPS under a PM2 cluster.
What I built
Biometric attendance pipeline
- ZKTeco fingerprint devices polled through an adaptive, holiday-aware pipeline.
- Every punch classified as entry, exit, or absent against per-class schedule windows; guardians receive an SMS within seconds.
- Handles 2,000-3,000 punches a day with cron reconciliation, health monitoring, and automatic recovery.
Academic core
- Exam results with auto-computed GPA and merit positions, behind a draft-to-publish workflow.
- Student promotion with per-step rollback and a full audit trail.
- CSV import/export for bulk exam results and admissions data.
Bengali-typography PDFs
- Client-side PDF generation with embedded Bengali fonts (@react-pdf/renderer): progress cards, admit cards, seat plans, and printable admission applications, all self-service instead of office queues.
Guardian messaging
- Rate-limited SMS service with retry/backoff, per-student deduplication, per-message delivery status, and an emergency kill switch.
Operational views
- 35 role-gated dashboard pages across seven roles, on a tag-invalidated RTK Query data layer with offline-persisted sessions.
- A full-screen “Now Teaching” board auto-refreshing every 30 seconds under a locked-down display account, plus attendance dashboards with absentee lists.
Decisions & trade-offs
An SMS kill switch as a first-class feature
A bug in an SMS loop is a real-money incident and a thousand angry guardians. The global kill switch, per-student deduplication, and rate limiting were built before scale, not after the first incident.
Holiday-aware adaptive polling
School calendars are irregular. The poller adapts its frequency to schedule windows instead of hammering the device around the clock, and cron reconciliation backfills anything missed.
Solo-operable by design
One engineer runs this part-time. Health monitoring, automatic recovery, and audit trails aren't nice-to-haves; they're what makes that possible.
Outcome
- The school runs on the platform daily. Attendance, results, fees, admissions, and printing are self-service.
- Guardians are notified of attendance within seconds of a fingerprint punch.
- Operated in production by one part-time engineer, by design.