A results-driven Senior Backend Engineer specializing in building robust enterprise architectures, high-performance APIs, and financial middleware solutions using the .NET ecosystem.

I focus on translating complex business requirements into maintainable, scalable, and secure production-grade software.

• Backend Technologies: ASP.NET Core, Web API, C#, Entity Framework Core, LINQ, OOP, ASP.NET MVC.
• Architecture & Design: Clean Architecture, CQRS, Modular Monolithic Architecture, Multi-Tenant Architecture.
• Databases & Caching: SQL Server, MySQL, SQLite, Redis.
• Security & Authentication: JWT, HMAC, Rate Limiting, Role-Based Access Control (RBAC).
• Tools & Utilities: Serilog, Quartz.NET, Hangfire, Git & GitHub, Postman, Jira.
• Frontend Familiarity: Angular, JavaScript (ES6), HTML5, CSS3, Sass, Bootstrap, Tailwind CSS, jQuery, Ajax.

An enterprise-grade commercial infrastructure management solution designed to streamline multi-branch Point-of-Sale (POS) operations, inventory management, and real-time storefront sales analytics.

Highlights:

• Engineered resilient transactional web services using Modular Monolithic architecture.
• Implemented the CQRS pattern to decouple read and write operations, improving performance by 40%.
• Designed and implemented Offline-First architecture for reliable operation in low-connectivity environments.
• Applied distributed Redis Caching for active sessions, reducing database load by 30%.

A secure B2B financial compliance gateway that automates tax validation and direct commercial invoice legalization with the Egyptian Tax Authority portal.

Highlights:

• Built robust API integration handlers to synchronize sales data from external platforms such as Shopify and Foodics.
• Developed automated batch data pipelines using scheduled Quartz.NET background jobs.
• Strengthened security with custom HMAC cryptographic signatures and tenant-based rate limiting.
• Implemented Multi-Tenancy support for secure data isolation across clients.

A multi-tenant SaaS platform tailored for accounting firms to manage client taxation lifecycles, payroll reporting, and historical ledger audits.

Highlights:

• Integrated government web portals to automate historical tax record retrieval, enabling accountants to efficiently generate and upload required tax reports.
• Refactored database schemas and indexes, accelerating financial report generation by 35%.
• Enforced strict Role-Based Access Control (RBAC) to secure multi-tenant endpoints and data boundaries.

• Distributed Systems: Designing resilient service boundaries and managing eventual consistency.
• Event-Driven Architecture: Leveraging message brokers for high-throughput asynchronous messaging.

• LinkedIn: https://www.linkedin.com/in/tony-isaac
• GitHub: https://github.com/tonyisaacG
• HackerRank: https://www.hackerrank.com/programmer2020s1
• Email: antonyisaacgayed@gmail.com