Senior Full-Stack .NET Engineer - AI Tools

Paychex is reimagining how businesses manage their workforce by bringing payroll, HR, benefits, and advisory services together into a single connected HCM platform. As Paychex and Paycor come together, we're combining innovative technology, data-driven insights, AI, and human expertise to help organizations work smarter, support their people, and achieve better business outcomes. This is an exciting time to join our team as we continue to invest in innovation, simplify client experiences, and shape the future of work. At Paychex, you'll have the opportunity to grow your career, make a meaningful impact, and be part of something bigger as One Paychex.
Responsibilities

• Design, develop, and deliver scalable software solutions that support business needs across the front end, back-end API, or agent/automation layer.
• Drive agentic development practices across a modern AI software delivery platform
• Build and operate services in Azure/Kubernetes, applying the security and data-protection practices required for the platform's tenant and credential data.
• Support production systems; troubleshoot technical issues using distributed tracing/telemetry and help ensure system stability.
• Build and evolve agent tooling and integrations — developer CLIs, tool registries, and automated workflow steps (running commands, invoking LLMs, creating pull requests, etc.).
• Participate in architecture and technical design discussions, contributing to system improvements across service boundaries.
• Improve testing, deployment, and monitoring processes to enhance software quality and reliability.
• Mentor engineers, share technical knowledge, and help remove technical roadblocks to keep projects moving forward.
• Perform code reviews and promote engineering best practices across the team.

Qualifications

• Strong experience with .NET/C# technologies (modern .NET, ASP.NET Core Web API, EF Core).
• 5+ years of hands-on experience in full lifecycle software development.
• Good knowledge of JavaScript/TypeScript and React.Hands-on experience building and running containerized services (Docker, Kubernetes) on Azure (AKS, App Service, or equivalent).
• Strong production-debugging instincts — able to reconstruct what actually happened from telemetry (distributed tracing, metrics, logs).
• Experience designing and developing microservices-based / distributed architectures.
• Experience with REST API design and with authentication/authorization (OAuth 2.0 / OIDC, Entra ID / Azure AD).
• Experience with CI/CD pipelines (e.g., GitHub Actions) and automated quality gates.
• Experience creating and maintaining automated tests.
• Experience with relational data stores (PostgreSQL) and an ORM (e.g., EF Core), including schema design and query optimization.

What's in it for you?

• A flexible work philosophy
• Generous paid time off
• Company paid private health insurance
• Company paid life and disability insurance
• Paid leave for illness, birth parents, non-birth parents, elder caregivers, marriage, adoption of a child and bereavement
• Inclusive and accessible Employee Assistance Program (EAP) to help with everyday challenges
• Christmas and Easter bonuses
• Work-from-home allowance
• Opportunity for strengthening expertise and skills through Paychex’s learning platform, including lessons in English

Not sure if you meet every requirement?

At Paychex, we know that great talent comes in many forms. If you're passionate about the role but don't check every box, we still encourage you to apply. You might be the right fit - either for this position or another opportunity with us.

Paychex is an equal opportunity employer. We are committed to fostering a respectful and inclusive workplace where all individuals are treated fairly and evaluated based on their qualifications, experience, and merit. We comply with all applicable federal, state, and local laws prohibiting discrimination in employment.