A commercial-grade bank payment integration engine built with .NET 9 Web API and Angular. It enables seamless multi-bank integrations, secure transactions, and scalable payment orchestration across enterprise environments. The system abstracts provider-specific APIs into pluggable bank adapters, reducing integration time and preventing vendor lock-in.
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Multi-Bank Adapters Clean provider model for onboarding new banks or payment gateways without rewriting core logic.
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Payment Orchestration Layer Handles workflow routing, validations, retries, multi-step flows, and transaction lifecycles.
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Secure Transaction Processing Token-based authentication, encryption, rate limiting, and request integrity.
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Enterprise-Grade Error Handling Structured exception model, retry policies, idempotency, and transaction recovery.
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Observability and Logging Centralized logging, diagnostic tracing, metrics, and full auditability.
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Modular Architecture Supports component isolation, horizontal scaling, and easy maintenance.
Backend: .NET 9 Web API
- Application Layer
- Domain Layer
- Infrastructure: Adapters, Repositories, Database
- Security + Identity
- Observability
Frontend: Angular
- Admin Dashboard
- Transaction Management UI
- Logs / Monitoring
- Integration Controls
- Separation of concerns
- Dependency inversion (providers injected, not hard-coded)
- Extendability via adapters
- Fail-safe transaction design
- Stateless API services where possible
- Minimal coupling
/src
├── api # .NET Web API
│ ├── Domain
│ ├── Application
│ ├── Infrastructure
│ ├── Adapters
│ ├── Orchestration
│ └── Tests
└── frontend # Angular UI
├── domains
├── shared
├── services
└── components
Adapters allow each bank integration to remain isolated:
- Each adapter implements a standard interface
- Each adapter handles its own auth, payload requirements, and API quirks
- The orchestration layer only depends on the interface — not the bank
This makes adding a new bank:
- Implement adapter interface
- Register the provider
- Deploy without touching existing integrations
- JWT (access + refresh)
- TLS enforced
- Rate limiting
- Request signing
- Audit logs
- Configurable role-based access
Optional enterprise features:
- HSM / secure vault integration
- PCI-DSS ready logging discipline
- KMS / Azure Key Vault / AWS Secrets Manager
- Structured logging
- Transaction trace IDs
- Error snapshots
- Provider-level metrics
- Real-time dashboards (UI layer)
- Unit tests for adapters and workflows
- Integration tests against sandbox APIs
- Contract tests for provider stability
- End-to-end tests simulating real transaction flows
- Mobile money adapter (Airtel/MTN/Zamtel)
- Background worker queue for async payments
- Anti-fraud rules engine
- Batch settlements
- Plugin system for 3rd-party integrations
- Event-driven architecture (Kafka/RabbitMQ)
- Fintech platforms needing multiple bank rails
- Merchant backends and settlement systems
- Enterprise integrations with legacy banking APIs
- Payment orchestration engines for online services
Contributions are welcome via feature requests, bank adapter additions, or performance improvements.