Senior Software Engineer - C#, .NET/.NET Core, Linux

This position is listed on behalf of a partner company, who manages all applications and next steps. Our partner is looking for a Senior Software Engineer - C#, .NET/.NET Core, Linux based in the United States. This is an exciting opportunity for a senior backend engineer to help shape the future of healthcare technology by building scalable, cloud-native services that improve how people access and experience care. In this role, you will design and develop robust APIs and distributed systems using modern Microsoft technologies while collaborating with multidisciplinary teams. You will contribute throughout the software development lifecycle, from architecture and implementation to testing and deployment. This position is ideal for an experienced engineer who enjoys solving complex technical challenges, improving system reliability, and mentoring other developers in a remote-first environment. Accountabilities Design, develop, test, deploy, and maintain scalable backend services and APIs using C#, .NET, and .NET Core. Build cloud-native applications and microservices designed for reliability, performance, and long-term scalability. Collaborate with product, quality assurance, UX, and engineering teams throughout the software development lifecycle to deliver high-quality solutions. Partner with platform teams to define and implement architectural best practices that improve system stability and operational efficiency. Participate in code reviews, technical discussions, and engineering practices that continuously improve code quality and development standards. Mentor junior and associate-level engineers by sharing knowledge, providing guidance, and promoting best practices across the development lifecycle. Troubleshoot, optimize, and enhance existing services while ensuring strong performance in distributed environments. Contribute to the evolution of backend architecture, cloud infrastructure, and software engineering processes. Requirements 4+ years of professional backend software development experience using C#, .NET, and .NET Core. Strong experience designing and developing APIs, backend services, and scalable software solutions. Hands-on experience working with Linux environments. Proven experience building cloud-based applications in environments such as AWS or Azure. Experience with containerization and orchestration technologies, including Docker and Kubernetes. Demonstrated ability to design and implement scalable microservices architectures. Experience working with messaging systems and event-driven architectures, with Kafka experience highly preferred. Strong understanding of software development lifecycle practices, testing methodologies, and engineering best practices. Excellent collaboration and communication skills with the ability to work effectively across technical teams. Ability to work independently in a fully remote environment while managing priorities effectively. Benefits Fully remote position available to candidates located in the United States. Comprehensive healthcare benefits, including medical, dental, vision, life, and disability insurance. 401(k) retirement savings plan. Health Savings Account (HSA) and Flexible Spending Account (FSA) options. Paid parental leave, including paternity leave. Childcare assistance programs. Tuition reimbursement opportunities. Employee assistance programs. Commuter benefits. Opportunity to work on impactful healthcare technology solutions. Collaborative engineering environment with opportunities for professional growth and mentorship. How Keystone AI works: We use an AI-powered matching process to ensure your application is reviewed quickly, objectively, and fairly against the role's core requirements. Our system identifies the top-fitting candidates, and this shortlist is then shared directly with the hiring company. The final decision and next steps (interviews, assessments) are managed by their internal team. We appreciate your interest and wish you the best! Why Apply Through Keystone AI? Data Privacy Notice: By submitting your application, you acknowledge that Keystone AI will process your personal data to evaluate your candidacy and share relevant information with the hiring employer. This processing is based on legitimate interest and pre-contractual measures under applicable data protection laws (including GDPR). You may exercise your rights (access, rectification, erasure, objection) at any time. #LI-CL1