Fintech · Full-stack
AjoCore.
Production-grade fintech backend that digitises Ajo, Esusu, and Adashe cooperative savings with automated virtual accounts, real-time webhook contribution tracking, and scheduled payout disbursement.
The brief
AjoCore modernises informal cooperative savings with a secure, transparent, and automated REST API. It supports ROSCA, ASCA, and personal saving cycles, automated Nomba virtual-account provisioning, HMAC-verified webhook contribution recording, idempotent payouts, and role-specific financial dashboards. The backend uses Clean Architecture across Domain, Application, Infrastructure, Persistence, and API layers, with CQRS via MediatR, FluentValidation, AutoMapper, Entity Framework Core with PostgreSQL, Hangfire, Serilog, Docker, Railway hosting, and a Vercel frontend.
Capabilities
- 01Multi-Scheme Saving Cycles
- Supports ROSCA rotation, ASCA accumulation, and personal savings goals, including maturity payouts, payout-order management, and early liquidation with a 5% penalty.
- 02Cooperative Group Management
- Provides group creation, invite links, direct and batch member additions, join requests, approvals, deactivation, removals, and date-filtered ledger views.
- 03Virtual Account Provisioning
- Automatically provisions a dedicated Nomba virtual account for each member-cycle combination, so contributions are recorded by transferring money rather than entering records manually.
- 04Webhook Contribution Recording
- Validates Nomba payloads with HMAC signatures and timestamps, enforces idempotency, records matching contributions in real time, and automatically reverses mismatched amounts.
- 05Automated Payout Disbursement
- Runs a daily Hangfire liquidation sweep for ROSCA, ASCA, and personal-cycle payouts. Transfers are idempotent, bank details are validated, and members receive payout notifications.
- 06Contribution Reminders
- Runs a daily Hangfire reminder service that emails members whose contributions are due within the next one to two days.
- 07Authentication and Authorisation
- Provides registration, email verification, JWT access and refresh-token rotation, password recovery, BVN-backed KYC, and Trader, CooperativeAdmin, and SystemAdmin access controls.
- 08Financial Dashboards
- Shows trader balances, cooperative and cycle aggregates, contribution and payout ledgers, system-wide statistics, live Nomba wallet balances, and controlled withdrawals.
- 09Profiles and Bank Services
- Supports role-based profile management, payout-bank updates, Nigerian bank listings, and account-name verification before payout details are saved.
- 10Reversal Engine
- Creates reversal-ledger entries for mismatched contributions, validates destination bank details, executes refunds, and sends an itemised HTML explanation.