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BEMER CRM
Full-stack CRM for medical device distributors
PythonStreamlitFirebaseStripePandas
Device inventory — own and partner-borrowed devices with full rental history
Client management — renters with contact details and transaction history
Rental overview — active rentals with availability and revenue tracking
Contract management — auto-generated contracts with client and billing details
Reminders — automated alerts for overdue rentals and upcoming actions
The Problem
BEMER medical device distributors in Hungary manage rentals, sales, clients, and contracts manually using spreadsheets and paper. There is no visibility into device availability, rental overlaps, or revenue. Contract generation is tedious and error-prone.
The Solution
- Built a full CRM in Streamlit + Firebase + Stripe
- Device inventory management (owned + partner-borrowed devices)
- Client management (renters + buyers) with contact details
- Rental transaction system with calendar-based availability checking
- "Possession Envelope Rule" — validates sub-rental dates fall within B2B possession windows
- Automated contract generation (HTML → PDF, client-side)
- Stripe subscription billing (free vs pro tier)
- Multi-entity billing support (individual + company)
- Google + Facebook OAuth with email verification
Architecture
Streamlit UI → Firebase Auth + Firestore → Stripe Billing
Results
Production app with real paying users
391 automated tests across 7 modules
Atomic batch writes for data consistency
Optimistic UI with intelligent cache invalidation
"Mum Test" UX philosophy — built for non-technical users