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Fintech / Rotating Savings
ROLE // LEAD SYSTEMS ARCHITECT & CORE DEVELOPER

Cowri

Rotating savings (Ajo/Esusu), multi-party bill-splitting, and automated Paystack DVA reconciliation.

RustGlideAPITokioPostgreSQLReact 19TanStackPaystack DVACloudflare
the problem

Informal rotating credit associations (Ajo/Esusu) and shared group expenses suffer from manual book-keeping errors, default risks, and reconciliation drift between bank transfers and platform ledgers.

the solution

Built a cryptographic double-entry ledger with automated Paystack Dedicated Virtual Account (DVA) reconciliation. Enforces atomic balance reservations across group cycles with zero double-crediting.

the system

Compiled Rust backend built on GlideAPI and Tokio with PostgreSQL transactional isolation. Fronted by a React 19 single-page application with TanStack Router and Query.

the hard part

Two-phase atomic debit/credit operations with idempotency keys guarantee zero ledger leakage across ROSCA cycles; automated Paystack webhook signature verification.

why this stack

Rust and GlideAPI provide sub-millisecond execution and compile-time correctness guarantees for multi-party financial state machines.

the innovation

Combines cultural rotating savings mechanics with institutional-grade ledger guarantees and zero-human-touch bank account creation.

the potential

Pan-African social liquidity and rotating group treasury platform.

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