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Senior Software Engineer with 5+ years of C#/.NET experience building cloud-native microservices and secure backend systems for regulated financial services. Hands-on with .NET 6, .NET 8, and .NET 10, including owning services end-to-end—API contracts, security, schema design, and Azure deployment. Experienced architecting core transaction infrastructure for a commercial bank, integrating payment gateways and webhooks, and delivering maintainable systems using Clean Architecture, SOLID, and domain-focused service design. Open to remote work, contract opportunities (via EOR/Deel), and relocation, with comfort working in Agile/Scrum environments.…Senior Software Engineer with 5+ years of C#/.NET experience building cloud-native microservices and secure backend systems for regulated financial services. Hands-on with .NET 6, .NET 8, and .NET 10, including owning services end-to-end—API contracts, security, schema design, and Azure deployment. Experienced architecting core transaction infrastructure for a commercial bank, integrating payment gateways and webhooks, and delivering maintainable systems using Clean Architecture, SOLID, and domain-focused service design. Open to remote work, contract opportunities (via EOR/Deel), and relocation, with comfort working in Agile/Scrum environments.

Josiah Onyeje

Back-End Developer, Programmer, Web Developer, +2

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Senior Software Engineer with 5+ years of C#/.NET experience building cloud-native microservices and secure backend systems for regulated financial services. Hands-on with .NET 6, .NET 8, and .NET 10, including owning services end-to-end—API contracts, security, schema design, and Azure deployment. Experienced architecting core transaction infrastructure for a commercial bank, integrating payment gateways and webhooks, and delivering maintainable systems using Clean Architecture, SOLID, and domain-focused service design. Open to remote work, contract opportunities (via EOR/Deel), and relocation, with comfort working in Agile/Scrum environments.…Senior Software Engineer with 5+ years of C#/.NET experience building cloud-native microservices and secure backend systems for regulated financial services. Hands-on with .NET 6, .NET 8, and .NET 10, including owning services end-to-end—API contracts, security, schema design, and Azure deployment. Experienced architecting core transaction infrastructure for a commercial bank, integrating payment gateways and webhooks, and delivering maintainable systems using Clean Architecture, SOLID, and domain-focused service design. Open to remote work, contract opportunities (via EOR/Deel), and relocation, with comfort working in Agile/Scrum environments.

Available to hire

Senior Software Engineer with 5+ years of C#/.NET experience building cloud-native microservices and secure backend systems for regulated financial services. Hands-on with .NET 6, .NET 8, and .NET 10, including owning services end-to-end—API contracts, security, schema design, and Azure deployment.

Experienced architecting core transaction infrastructure for a commercial bank, integrating payment gateways and webhooks, and delivering maintainable systems using Clean Architecture, SOLID, and domain-focused service design. Open to remote work, contract opportunities (via EOR/Deel), and relocation, with comfort working in Agile/Scrum environments.

Skills

Experience Level

Expert

Expert

Expert

Expert

Expert

Expert

Expert

Intermediate

Beginner

Language

English

Advanced

Work Experience

Technical Mentor / Coding Instructor at Self-Employed

January 1, 2026 - Present

Provided 1-on-1 mentoring and code review for developers learning .NET/C#, covering backend fundamentals, API design, and career readiness. Delivered structured guidance and mock technical interviews to support mentees preparing for backend engineering roles.

Backend Software Engineer (.NET) at Suntrust Bank

August 1, 2024 - June 1, 2026

Designed and built ASP.NET Core Web APIs for core banking workflows using SOLID principles and Clean Architecture. Owned backend services supporting secure financial transaction flows alongside compliance/risk requirements. Wrote and tuned SQL queries and stored procedures to improve performance for high-volume production transaction processing. Partnered with frontend engineers to deliver end-to-end banking features and maintain consistent release cadence through Agile/Scrum with Git-based workflows and code reviews. Refactored legacy areas to reduce duplication and improve maintainability.

Independent Backend Software Engineer (Freelance, Part-Time) at Self-Employed

January 1, 2023 - Present

Designed and shipped production fintech backend systems including interbank payment processing, virtual card middleware, and identity verification services. Built normalized database schemas and optimized SQL across SQL Server and PostgreSQL. Deployed services to Render with publicly accessible Swagger/OpenAPI docs to enable independent API testing. Conducted client discovery and scoping, maintained professional Git workflows, and delivered demo-ready end-to-end solutions when needed.