Backend .net Engineer - Ussd & Telco Charging

ServTech Rwanda is looking for a
Mid Level Backend .NET Engineer to help build large-scale products across Africa, with a focus on USSD and telco charging in Rwanda.
YOUR IMPACT

• Design and build backend services at scale, owning work from scoping and design through implementation, testing, deployment, and optimisation.
• Maintain a high-performance platform with strong uptime and speed, tuning high-throughput services (concurrency, rate limiting, back-pressure, circuit breaking).
• Lift engineering quality through design discussions, code reviews, and modern tools and patterns.
• Improve reliability, security, and developer workflows with better CI/CD, test automation, and tooling.
• Partner with Product, Design, and BI to deliver business-critical features for users across Africa.
• Design and build USSD menus, applications, and short-code flows for Rwanda, handling timeouts, languages, and device differences.
• Integrate with Rwandan MNOs (e.g., MTN Rwanda, Airtel Rwanda) for USSD, charging, and Mobile Money, and build charging engines (real-time charging, balance checks, refunds, retries, idempotency).
• Create secure, low-latency APIs and adapters for USSD gateways, charging platforms, and wallet providers, ensuring compliance with RURA, privacy, KYC/AML, and operator rules.
  

Our Requirements

• 3 years of advanced C#/.NET development experience (strong in .NET Core).
• Recent, proven experience delivering USSD services and/or telco charging integrations in Rwanda (must-have).
• Strong SQL skills (schema design, complex queries, stored procedures).
• Solid knowledge of service architecture: stateless services, caching, messaging, RESTful APIs.
• Hands-on experience with Docker and CI/CD; comfortable with automated testing.
• Production experience on a public cloud (AWS preferred).
• Experience with Redis or a similar NoSQL store.
• Strong performance diagnostics and tuning skills (profiling, memory/CPU, DB and cache).
• Proactive, results-driven, and a clear communicator in English.
  

NICE TO HAVE:

• Experience with Mobile Money integrations, SMPP/SMS gateways, OAuth2/OpenID Connect.
• Familiarity with observability tooling (Prometheus, Grafana, OpenTelemetry) and resiliency patterns.
• Knowledge of other African markets and telco integration specifics.
  

WHAT WE OFFER:

• Discretionary Salary Reviews 💵
• Medical insurance (applicable after successful completion of the probation period)
• Employer Pension Contributions (RSSB) 💰
• Personalized Learning & Development Opportunities 📖
• Exciting Team-Building, Welfare & Social Events 😎
• Long-Term Career Growth Opportunities 🎯
• 18 Days of Annual Leave 📢
• Marriage Leave Vacation 💍
• Enhanced Maternity & Paternity Leave 💙

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