Senior C#/.Net Software Engineer Objectives: You will work closely with a geographically diverse engineering organization and will be embedded within one of our core domain teams. Beyond contributing code, this role is expected to actively shape architectural direction through hands on guidance, clear technical judgment, and pragmatic systems thinking.Your initial focus will be learning the existing architecture, domain models, and processes across legacy and modern components of the platform. Over time, you will take ownership of architectural iteration within your domain, influence cross-team patterns, and help guide the long-term modernization of the platform in alignment with broader portfolio initiatives.In this role, success is measured not only by features delivered, but by improved system clarity, stronger service boundaries, reduced architectural friction, and the team’s ability to move faster and more safely over time. Lead by example through thoughtful design, high-quality code, clear documentation, and constructive technical discourse.Responsibilities: • Work effectively with a geographically distributed engineering team and cross-functional partners in a continuously evolving environment.• Apply systems thinking to backend and platform design, accounting for feedback loops, constraints, and second-order effects across multiple domains and teams.• Ramp up quickly on an evolving platform that includes a legacy PHP monolith within the platform that is being incrementally evolved into modern .NET backend microservices, along with MySQL schemas and data models that support core business workflows.• Build high-quality .NET services with clear domain intent, well-defined API contracts, and robust validation.• Own backend services end-to-end within your domain, acting as the internal expert on their intent, design, lifecycle, and evolution—including enhancement, refactoring, and deprecation.• Partner with senior engineering staff and architects to refine and evolve system architecture, service boundaries, and modernization strategy.• Improve legacy behaviors by introducing explicit, action-driven backend transitions and modern workflow patterns that increase clarity, maintainability, and testability.• Support platform reliability by writing high-quality, testable code and collaborating with QA to ensure strong unit, integration, and API coverage across critical workflows.• Participate in code reviews, technical discussions, and cross-team knowledge sharing to raise the bar on consistency, maintainability, and engineering culture.• Troubleshoot and resolve complex issues involving multi-step workflows, state transitions, service interactions, and legacy-to-modern integration points.• Contribute to architecture documentation, onboarding materials, and technical design records to support long-term team scalability.• Collaborate with platform and DevOps teams to influence CI/CD, deployment, observability, and runtime concerns, while ensuring services meet security, compliance, scalability, and availability standards.• Support compliance initiatives with secure coding, documentation, and process rigor.Required Competencies: 10+ years of experience as a backend software engineer with deep expertise in C# / .NET (Core/5+).Strong experience with relational databases (MySQL or similar), including data modeling and safe migration patterns.Experience incorporating AI rules, context, and tools into the development workflow to increase team efficiency (GitHub Copilot, LLM chatbots, etc.).Experience with Java-based backend services, particularly in environments with mixed or transitioning technology stacks.Proven ability to understand and improve large, legacy systems while making and defending architectural decisions in complex, long-lived environments.Experience navigating tradeoffs between speed, correctness, scalability, and maintainability.Experience designing and maintaining RESTful APIs, backend workflows, or state-driven domain logic.Strong debugging and analytical skills, especially across complex, workflow-heavy systems.Excellent communication skills and ability to collaborate effectively with a distributed, global engineering team.Preferred Competencies: Experience with PHP or legacy-application modernization.Familiarity with multi-tenant SaaS environments or systems with rich content, workflow, or approval logic.Prior experience as a technical lead or architect for backend services.Experience with automated testing, including end-to-end or behavior-driven testing.Strong understanding of modern service architecture patterns (microservices, domain boundaries, facades, API gateways).Work Structure:Red Oak values the energy and creativity that comes from working together in person. To support this cultural element, this hybrid role is based out of our North Austin HQ with a minimum of 3 days (Tuesday-Thursday) in the office each week.Benefits:Equity UnitsHealthcare Insurance5% 401K matchUnlimited PTOAdditional Information:This position is NOT eligible for Visa sponsorship.