Matthew Ballew

Led modernization of enterprise payment and settlement systems into a cloud-native distributed microservices architecture to support real-time financial processing and compliant transaction operations. Migrated legacy settlement services to .NET 8 microservices using Clean Architecture, DDD, CQRS, and event-driven patterns to scale payment workloads over $10M monthly. Built dashboards with Angular 16 and RxJS to improve operational visibility and reduce manual investigations. Designed distributed transaction orchestration with ASP.NET Core Web APIs and Azure Service Bus pub/sub, cutting reconciliation delays and boosting settlement throughput by 35%. Implemented asynchronous payment workflows with background services, SQL Server persistence, and idempotency validation to minimize duplicates. Created RESTful APIs and GraphQL gateway layers with Swagger/OpenAPI to accelerate onboarding of partners by ~32%. Enforced secure authentication with OAuth2, OpenID Connect, Microsoft Entra ID, JW

Led modernization of enterprise payment and settlement systems into cloud-native distributed microservices architecture supporting real-time financial processing and compliance-driven transaction operations. Migrated legacy settlement services to .NET 8 microservices leveraging Clean Architecture, DDD, CQRS and event-driven design. Built enterprise transaction monitoring dashboards with Angular 16 and RxJS; implemented distributed transaction orchestration with ASP.NET Core Web APIs and Azure Service Bus pub/sub; designed asynchronous payment workflows with background services, SQL Server persistence, and idempotency validation to reduce duplicate transactions. Developed RESTful and GraphQL integrations with partner onboarding, secured OAuth2/OpenID Connect authentication with JWT and RBAC; containerized deployments with Docker and Kubernetes/AKS; established centralized observability (Azure Application Insights, Grafana) and optimized high-concurrency SQL workloads. Created Python-bas

Modernized legacy ASP.NET WebForms/MVC monolithic healthcare applications into modular ASP.NET Core service-oriented architecture; built clinician dashboards using React; implemented interoperability using FHIR/HL7; developed backend services with AWS SNS/SQS for patient notifications; designed hybrid enterprise integration for SOAP and REST; migrated critical services to AWS EC2/Lambda/S3; built HIPAA-compliant audit logging and tracing; optimized SQL Server analytics; implemented blue-green deployment for healthcare APIs; automated document processing and patient intake with Python/AWS; collaborated with stakeholders in Agile environments; mentored engineers.