Backend Developer - AI Data Services

Seattle

**Backend Developer --- AI Data Services** **About The Role** What if your C# expertise could directly shape the infrastructure powering the next generation of AI? We're looking for a senior-level full-stack engineer to design and build the data pipelines, annotation tooling, and evaluation systems that leading AI labs depend on to train and improve their models. This is a fully remote contract role with flexible hours. You'll work on real production systems --- not toy projects --- alongside data, research, and engineering teams at the forefront of AI development. * 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 large-scale AI data pipelines and evaluation workflows * Develop full-stack backend tooling and services for data annotation, validation, and quality control * Improve the reliability, performance, and safety of existing C# codebases * Collaborate with research and engineering teams to support model training and evaluation infrastructure * Identify bottlenecks and edge cases across data and system behavior, then implement scalable, production-ready fixes * 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 skills * Experienced full-stack developer with a strong systems programming background * 5+ years of professional experience writing production-grade C# * Skilled in data modeling and database access using ORM frameworks or micro-ORMs for high-performance SQL interactions * Proven experience building secure, well-documented endpoints for data access and manipulation * Able to commit reliably to 20--40 hours per week **Nice to Have** * Prior experience with data annotation, data quality systems, or evaluation pipelines * Familiarity with AI/ML workflows, model training, or benchmarking infrastructure * Experience with distributed systems or developer tooling **Why Join Us** * Work on cutting-edge AI infrastructure projects alongside leading research labs * Fully remote and flexible --- work when and where it suits you * Freelance autonomy with the structure and substance of high-impact, meaningful work * Make a direct, tangible contribution to the systems that shape how AI learns and improves * Potential for ongoing work and contract extension as new projects launch