Senior .NET Backend / API Integration Engineer – Conversational AI Orchestration

Job Title: Senior .NET Backend / API Integration Engineer – Conversational AI Orchestration

Work Setup: Full onsite

Location: Quezon Avenue, Eton Centris, Manila

Work Shift: Mid to Night shift, with at least 2 hours daily overlap with US Central Time (CST)

Relevant years of experience: Minimum 8+ years (non-negotiable)

Headcount: 1

Job Description

We're looking for an experienced, self-driven Senior .NET Backend / API Integration Engineer for a healthcare conversational AI program in Agile / AIDLC working client environment. You'll lead the design, build and maintenance of the backend services and orchestration layer that route provider calls between authentication, multiple third-party voice and AI agents and live-agent escalation.

Primary Responsibilities:

• Own the technical design of backend services and the orchestration layer using ASP.NET Core, C#, and Entity Framework.

• Build and maintain an orchestration and routing layer that manages several voice and AI agents, including hand-offs within a single call.

• Design, develop, secure and maintain RESTful APIs for internal and external integrations.

• Integrate with third-party conversational AI and voice platforms, contact center/IVR systems and enterprise healthcare platforms.

• Develop and support API authentication and authorization

• Provide technical leadership: guide and mentor engineers, set coding standards and lead code reviews.

• Work with Architects on solution design, technical decisions and estimates.

• Write clean, scalable, well-documented code that follows best practices.

• Collaborate with Product Owners, QA Engineers, Architects, DevOps and contact center business teams.

• Drive unit testing and continuous integration practices.

• Troubleshoot and resolve complex production issues and improve performance.

Must Have

• College Graduate

• 8+ years of software development using .NET technologies, with a strong backend focus.

• Hands-on experience with Agile/Scrum and the AI-Driven Development Lifecycle (AIDLC), using AI-assisted tools in the client's environment.

• Proficiency in C#, ASP.NET Core, Web API, and Entity Framework.

• Strong hands-on experience in API development, API integration and microservices architecture.

• Proven experience designing orchestration or routing layers that coordinate multiple services or agents.

• Experience designing and consuming RESTful APIs, webhooks and real-time or streaming interfaces (e.g., WebSockets).

• Knowledge of API security standards, including OAuth 2.0, JWT, authentication and authorization.

• Experience leading or mentoring development teams and owning technical delivery.

• Basic understanding of AI concepts and AI-powered applications – GitHub Copilot, Claude etc..

Nice to Have:

• Contact center or IVR integration experience (call transfer, caller authentication, live-agent escalation).

• Experience consuming LLM or AI agent APIs and applying guardrails (e.g., Azure OpenAI, Semantic Kernel).

• Event-driven integration using Azure Service Bus, Kafka, or similar.