Senior .NET AI Engineer — AI-Driven Backend Orchestrator

Sonata Software (SonataOne); San Antonio (TX); On-site; USD 120,000 - 180,000; Full time

Job summary

Sonata Software is seeking a senior backend engineer to design, develop, and maintain scalable backend services and AI-powered agent systems using C#, .NET Core, and AWS. You will build agent runtime orchestration and ensure secure tool integrations across internal APIs, external services, and databases.

The role emphasizes automated testing, observability, and performance monitoring, with strong focus on security boundaries, authentication, and CI/CD pipelines.

Qualifications

• 8+ years of hands-on software development experience, with strong expertise in C#, .NET Core, ASP.NET Core, REST APIs, and backend service development.
• 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.
• 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.
• Mortgage knowledge is a Plus

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/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.

Skills

C#

NET Core

ASP.NET Core

REST APIs

Backend services

AI-powered apps

Agent orchestration

AWS

Security best practices

CI/CD

Tools

Lambda

API Gateway

SQS

SNS

ECS/EKS

CloudWatch

IAM

Job description

Sonata Software is seeking a senior backend engineer to design, develop, and maintain scalable backend services and AI-powered agent systems using C#, .NET Core, and AWS. You will build agent runtime orchestration and ensure secure tool integrations across internal APIs, external services, and databases.

The role emphasizes automated testing, observability, and performance monitoring, with strong focus on security boundaries, authentication, and CI/CD pipelines.