Senior .NET AI Engineer

Sonata Software • San Antonio, TX

3d • Remote

About The Position

Sonata Software is seeking a Senior .NET AI Engineer to design, develop, and maintain scalable backend services and AI-powered agent systems using C#, .NET Core, and AWS. The role focuses on agent runtime orchestration, including task execution, workflow management, context handling, and coordination between agents and tools. It also involves building secure integrations with APIs, external services, databases, and enterprise applications, and defining explicit contracts and schemas for agent interactions and tool invocation.

The engineer will develop evaluation frameworks for agent accuracy, reliability, performance, and consistency; establish observability through logging, tracing, metrics, monitoring, and execution tracking; and implement security boundaries and safeguards for AI agent execution. The role also includes deploying, monitoring, and optimizing applications using AWS, CI/CD pipelines, and cloud-native practices. The position is based remotely in Brazil and requires 8 or more years of experience. Mortgage knowledge is a plus.

Sonata Software is an Equal Opportunity Employer. All qualified applicants receive consideration without regard to protected characteristics.

Requirements

• At least 8 years of hands-on software development experience, with strong expertise in C#, .NET Core, ASP.NET Core, REST APIs, and backend service development.
• Practical experience building AI-powered applications, agentic workflows, or autonomous/semi-autonomous agent systems.
• Strong understanding of agent runtime orchestration, tool calling, workflow execution, context management, and failure recovery.
• Experience integrating LLMs and AI services through APIs, SDKs, or agent frameworks.
• Strong knowledge of API design, explicit interface contracts, structured data formats, and distributed systems.
• Hands-on experience with AWS services such as Lambda, API Gateway, SQS, SNS, ECS/EKS, CloudWatch, and IAM.
• Experience implementing automated testing, evaluation pipelines, observability, and performance monitoring.
• Strong understanding of application security, secure coding practices, identity management, access controls, and secrets management.
• Experience with Git, CI/CD pipelines, automated deployments, and Agile development methodologies.
• Excellent problem-solving, debugging, communication, and collaboration skills.

Nice To Haves

• Mortgage knowledge.

Responsibilities

• Design, develop, and maintain scalable backend services and AI-powered agent systems using C#, .NET Core, and AWS.
• Build agent runtime orchestration capabilities, including task execution, workflow management, context handling, and coordination between agents and tools.
• Develop secure and reliable tool integrations with internal APIs, external services, databases, and enterprise applications.
• Define explicit contracts, schemas, and interfaces for agent interactions, tool invocation, structured inputs and outputs, and error handling.
• Implement evaluation frameworks to measure agent accuracy, reliability, performance, and consistency using automated tests and repeatable test scenarios.
• Establish observability through structured logging, distributed tracing, metrics, monitoring, and end-to-end execution tracking.
• Implement security boundaries, authentication, authorization, secrets management, input validation, and safeguards for AI agent execution.
• Deploy, monitor, and optimize applications using AWS services, CI/CD pipelines, and cloud-native engineering practices.

What This Job Offers

• Job Type: Full-time
• Career Level: Senior
• Education Level: No Education Listed