Senior Software Engineer (C#/.NET & AI)

WEX•Chicago, IL

1d•$121,500 - $145,500•Remote

About The Position

At WEX, we simplify the business of running a business. Our WEX Benefits solutions reduce complexity and help employers manage the cost and administration of employee benefits. We are looking for passionate technologists, collaborators, and problem solvers to join our Benefits Technology team as we build the next generation of employer benefits platforms and services. As a Senior Software Engineer, you will work closely with Product Managers, customers, and engineering peers to understand the challenges employers face in the evolving benefits landscape. You will design and deliver scalable, high-quality solutions using modern engineering practices, including test-driven development and cloud-native architectures. You will have the opportunity to contribute to mission-critical systems, influence technical direction, and help shape engineering standards across the team.

Requirements

7+ years of software engineering experience
Strong background in backend development, distributed systems, and scalable architecture
Proficiency in modern backend technologies such as C#, .NET, Java, or Python
Strong understanding of data structures, algorithms, and object-oriented design
Experience building and consuming REST APIs
Hands-on experience with React or modern UI frameworks
Experience with relational and NoSQL databases (e.g., SQL Server, PostgreSQL, MySQL, MongoDB)
Strong knowledge of CI/CD pipelines and Git-based workflows
Experience with cloud-native development in AWS or Azure
Understanding of software security principles and OWASP guidelines
Experience writing unit tests and maintaining high test coverage
Familiarity with Agile development methodologies
Proven ability to deliver complex projects on time
Experience with cloud services (AWS or Azure), including IAM, compute, storage, and API services
Familiarity with containerization using Docker and orchestration using Kubernetes
Exposure to CI/CD tools such as GitHub Actions, GitLab CI, or Jenkins
Basic understanding of Infrastructure-as-Code (Terraform preferred)
Familiarity with observability tools (Prometheus, Grafana, CloudWatch, Azure Monitor)
Familiarity with LLM concepts and frameworks such as LangChain, LlamaIndex, LangGraph, or CrewAI
Exposure to Retrieval-Augmented Generation (RAG) and interest in evolving toward Agentic RAG systems
Understanding of agentic workflows including tool use (function calling) and state management
Awareness of vector databases (e.g., Pinecone, Milvus) and semantic search concepts
Interest in emerging protocols such as Model Context Protocol (MCP)
Experience or curiosity in building AI-native features and LLM-based automation in CI/CD pipelines
Bachelor’s degree in Computer Science, Software Engineering, or related field
Strong collaboration skills in agile, cross-functional, and distributed teams
Ability to communicate technical concepts and trade-offs clearly to both technical and non-technical stakeholders
Proven ability to work effectively in geographically distributed teams
Self-driven, proactive, and highly accountable for deliverables
Continuous learner with strong interest in evolving cloud and AI technologies
C# / .NET (or equivalent backend language such as Java or Python)
React
REST API development (ASP.NET or equivalent frameworks)
Docker
Kubernetes
SQL & NoSQL databases
Cloud platforms (AWS / Azure)
CI/CD pipelines
Event-driven architecture

Nice To Haves

Terraform
Helm / ArgoCD
GitHub Actions
GraphQL
Kafka
Azure advanced services

Responsibilities

Partner with Product and stakeholders to understand customer challenges and translate them into technical solutions
Design, build, test, and deploy scalable, secure, and high-quality software solutions
Use data to measure outcomes, validate assumptions, and drive engineering decisions
Develop and maintain microservices and event-driven architectures
Strengthen engineering practices including TDD, BDD, and CI/CD automation
Support production systems through monitoring, incident response, and continuous improvement
Identify performance bottlenecks and optimize systems for scalability and reliability
Mentor peers and contribute to a culture of technical excellence and continuous learning
Take ownership of work, operate independently, and deliver high-quality outcomes with minimal supervision