Backend Developer - AI Data Services

Backend Developer — AI Data Services About The Role What if your C# expertise could directly shape the infrastructure powering next-generation AI? We're looking for a Senior C# Full-Stack Engineer to build and optimize the data pipelines, annotation tooling, and evaluation systems that leading AI labs depend on every day. This is a fully remote contract role with meaningful, high-impact work. You won't be maintaining legacy CRUD apps — you'll be solving real engineering problems at the frontier 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 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 production C# codebases • Collaborate with data, research, and engineering teams to support model training and evaluation infrastructure • Identify bottlenecks and edge cases in 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 • Full-stack developer with a strong systems programming background • 5+ years of professional experience writing production-grade C# • Experienced in data modeling and database access using ORM frameworks or micro-ORMs for high-performance SQL interactions • Proven ability to build secure, well-documented endpoints for data access and manipulation • Able to commit 20–40 hours per week consistently Nice to Have • Prior experience with data annotation, data quality pipelines, or evaluation systems • Familiarity with AI/ML workflows, model training, or benchmarking infrastructure • Experience with distributed systems or developer tooling at scale Why Join Us • Work on real production systems alongside researchers and engineers at leading AI labs • Fully remote and async-friendly — work from wherever you do your best work • Freelance autonomy with the structure and consistency of ongoing, meaningful project work • Gain direct exposure to cutting-edge AI development at the infrastructure level • Potential for extended engagement as projects evolve and new workstreams launch