Sharpa Servora (BAKİYE)

A live digital balance, payment and operational management platform running for Gördes Municipality in Manisa, Türkiye.

Developed at OZFILIZ YAZILIM VE BILISIM TEK. SAN. TIC. LTD. STI. The backend and the mobile applications were built entirely by me; this page describes my own engineering scope.

Platform scope

Citizen balance loading and controlled spending across municipal locations.
Online, card and cash top-up flows with full transaction history.
QR, NFC HCE and physical card payment scenarios.
POS terminals, branch operations, restaurant workflows and reporting.

Architecture and the balance engine

The system is a modular monolith organized as vertical slices with CQRS separation, so each business capability owns its own read and write path instead of sharing one generic service layer. Balances are handled by a hybrid ledger + snapshot engine: every movement is an append-only ledger entry, and periodic snapshots keep current-balance reads fast without making the snapshot the source of truth.