Card Issuing Platform on Microsoft Azure

Azure, Payments, Microservices

Azure Kubernetes Service API Management SQL Databases Redis Cache Blob Storage Service Bus Managed Identities Azure DevOps Terraform GraphQL

Overview

Designed and deployed a modular API platform for Card Issuing and Financial Institution integrations, leveraging Azure-native services for scale, compliance, and extensibility. The solution enabled seamless integration with payment networks like Visa and MasterCard, while decoupling processing flows across Auth, Clearing, Issuing, and Reporting.

PCI-DSS Compliance

The platform was designed with security and compliance as core principles, ensuring PCI-DSS readiness through:

Strict separation of API tier and secure data layer
Encrypted data in transit and at rest
Comprehensive audit logging and monitoring
Least privilege access controls via Azure Active Directory

Architecture Summary

Azure Kubernetes Service

Containerized services for Authorization, Clearing, Issuing, Bank, and Reporting APIs

Azure API Management

Gateway for external integrations from card sites, FTP, and banks

SQL Databases

Persistent storage for transaction and account data

Redis Cache

High-performance caching for real-time transaction processing

Blob Storage

Storage for transaction logs, reports, and audit data

Service Bus

Event-driven communication and downstream processing

Managed Identities

Authentication with Active Directory integration

Azure Monitor

Full observability and telemetry with Log Analytics and Application Insights

Azure DevOps

CI/CD pipelines integrated with GitHub for source and secrets

Architecture Diagram: Card & bank integrations, API gateway, services, and service bus connections

Design Considerations

PCI-DSS readiness ensured by separation of API tier and secure data layer
CI/CD implemented using Azure DevOps Pipelines, integrated with GitHub for source and secrets
Config-as-code managed via Terraform for infrastructure automation

Engineering Practices

Integration tests embedded within deployment pipeline with rollback logic
Rate-limiting and throttling enabled via API gateway policies
GraphQL added to the Reporting API to provide flexible querying across settlements

Impact Delivered

35%

Reduction in transaction reconciliation time through API-driven clearing

Enabled onboarding of new banks with reduced developer intervention

1000s

Scaled to handle thousands of card issuance requests per minute with load-tested SLAs

Key Differentiators

What Set This Platform Apart

Deep Observability

Layered observability and security throughout the platform, enabling real-time monitoring and rapid issue resolution

Flexible API Versioning

Comprehensive API versioning and documentation via OpenAPI, making integration seamless for partners

Secure Communication Model

Secure, asynchronous communication model supporting complex transaction processing workflows

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