Simbarashe Amos Nyamusa

Senior Full-Stack Developer

Specializing in .NET, Payment Gateway Integration & Enterprise System Modernization

5+ Years Experience
500K+ Users Served
40% System Downtime Reduction
300% Performance Improvement
C# / .NET Core SQL Server Entity Framework REST APIs HTMX & Alpine.js Payment Gateways Microservices

Featured Projects

Demonstrating expertise in full-stack development, payment integration, and system architecture

💳 Live Demo

Payment Gateway Simulator

Real-world payment processing system

Complete mobile money transaction processing with status monitoring, automated retries, and comprehensive analytics. Built to mirror payment infrastructure.

ASP.NET Core HTMX SQL Server Alpine.js
View Code Live Demo
📊 Live Demo

Telecom Billing Dashboard

Customer management & billing system

Comprehensive billing solution with invoice generation, payment tracking, service activation, and revenue analytics for operations.

ASP.NET Core Entity Framework HTMX Chart.js
View Code Live Demo
🎫 Live Demo

Support Ticket System

Customer service management platform

Real-time ticket management with priority levels, agent dashboard, SLA monitoring, and comprehensive reporting capabilities.

ASP.NET Core SignalR HTMX Alpine.js
View Code Live Demo
📱 Live Demo

SMS Campaign Manager

Bulk messaging & analytics platform

Enterprise SMS solution with template management, campaign scheduling, delivery tracking, and cost analytics using Infobip API andd gikko.

ASP.NET Core Infobip API Background Jobs HTMX
View Code Live Demo
🔗 Live Demo

API Integration Dashboard

REST API monitoring & management

Comprehensive API monitoring with endpoint tracking, request/response logging, performance metrics, and health checks.

ASP.NET Core REST APIs SQL Server HTMX
View Code Live Demo

Professional Experience

Building enterprise systems at scale in the telecommunications industry

Senior Software Developer

TelOne Zimbabwe

January 2021 - Present | Harare, Zimbabwe

  • Led digital transformation initiatives migrating legacy systems to modern .NET applications serving 500,000+ telecom subscribers
  • Developed payment gateway integrations with Ecocash, implementing robust error handling and automated retry mechanisms
  • Architected and implemented RESTful APIs for billing system integration, achieving 99.5% data accuracy
  • Reduced system downtime by 40% through proactive monitoring and optimized architecture
  • Optimized high-volume data processing handling 1M+ daily records, improving speed by 300%
  • Established CI/CD pipelines reducing deployment time by 60%
  • Mentored junior developers and led cross-functional teams

IT Systems Coordinator

Easi Group

June 2020 - December 2020 | Harare, Zimbabwe

  • Managed enterprise systems and IT infrastructure across 5 subsidiary companies supporting 200+ users
  • Administered Active Directory, Microsoft 365, and business-critical applications
  • Led system migration projects with zero data loss
  • Implemented disaster recovery protocols ensuring 99.9% business continuity

Technical Skills

Full-stack expertise with proven track record in enterprise environments

Backend Development

  • C# / .NET Core / .NET Framework
  • Entity Framework Core
  • RESTful API Design
  • Microservices Architecture
  • Payment Gateway Integration
  • Background Job Processing

Database & Performance

  • SQL Server / PostgreSQL
  • T-SQL & Stored Procedures
  • Query Optimization
  • Database Indexing
  • High-Volume Processing (1M+ records/day)
  • Caching Strategies

Frontend & Modern Web

  • HTMX & Alpine.js
  • JavaScript / TypeScript
  • HTML5 / CSS3
  • AngularJS / React
  • Tailwind CSS
  • Responsive Design

DevOps & Tools

  • Git / GitHub
  • CI/CD Pipelines
  • DevSecOps
  • Docker
  • Visual Studio / VS Code
  • Agile / Scrum

Specialized Knowledge

  • Ecocash Payment Integration
  • SMS Gateway (Infobip)
  • Telecom Billing Systems
  • Legacy System Modernization
  • Enterprise System Integration
  • Transaction Monitoring

AI-Enhanced Development

  • Claude Code
  • GitHub Copilot
  • AI-Assisted Debugging
  • Modern Dev Workflows

Get In Touch

Let's discuss how I can contribute to your team

Or reach me directly:

📧 simbarashenyamusa@gmail.com

📱 (+263) 775 006 615