C# Infrastructure Engineer - Data Pipelines

Seattle

**C# Infrastructure Engineer --- AI Data Pipelines** **About The Role** What if your C# engineering skills could directly shape the infrastructure powering the world's most advanced AI systems? We're looking for a senior C# engineer to design and build the high-performance data pipelines, annotation tooling, and evaluation infrastructure that leading AI labs depend on to train and improve next-generation models. This is a fully remote, flexible contract role for an experienced engineer who wants meaningful, high-impact work --- without the overhead of a full-time commitment. * Organization: Alignerr * Type: Hourly Contract * Location: Remote * Commitment: 20--40 hours/week **What You'll Do** * Design, build, and optimize high-performance C# systems supporting AI data pipelines and model evaluation workflows * Develop full-stack tooling and backend services for large-scale data annotation, validation, and quality control * Improve reliability, performance, and safety across existing C# codebases * Identify bottlenecks and edge cases in data and system behavior, then implement scalable, resilient fixes * Collaborate with data, research, and engineering teams to support model training and evaluation workflows * Participate in synchronous design reviews to iterate on architecture and implementation decisions **Who You Are** * Native or fluent English speaker with clear written and verbal communication * Full-stack developer with a strong systems programming background * 5+ years of professional experience writing production-grade C# * Deep experience building streaming data pipelines using asynchronous streams and reactive programming concepts * Skilled at optimizing I/O-bound operations and implementing resilient retry policies for distributed data ingestion * Able to commit 20--40 hours per week with reliable availability **Nice to Have** * Prior experience with data annotation, data quality, or AI evaluation systems * Familiarity with AI/ML workflows, model training, or benchmarking pipelines * Experience with distributed systems architecture or developer tooling **Why Join Us** * Work directly on production systems used by leading AI research labs * Fully remote and flexible --- structure your hours around your life * Freelance autonomy with the depth and consistency of real, ongoing engineering work * Make a tangible impact on the infrastructure shaping the future of AI * Potential for ongoing work and contract extension as projects scale