Senior Backend Engineer (C#) - AI Data Platform
Senior Backend Engineer (C#) — AI Data Platform 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 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 working on real production systems at the frontier of AI development. If you're a seasoned backend engineer who wants meaningful, high-impact work — this is it. 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 backend services and tooling for large-scale data annotation, validation, and quality control Improve reliability, performance, and safety across existing 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 5+ years of professional experience building scalable backend services in C# Strong systems programming background with full-stack development experience Deep expertise in modern frameworks for RESTful APIs and RPC services Experienced integrating cloud-native data services and orchestrating workflows via message bus architectures Able to commit 20–40 hours per week with reliability and consistency
Nice to Have
Prior experience with data annotation, data quality pipelines, or model evaluation systems Familiarity with AI/ML workflows, model training, or benchmarking infrastructure Background in distributed systems design or developer tooling
Why Join Us
Work directly on cutting-edge AI projects alongside the world's leading research labs Fully remote and flexible — structure your hours around your life Freelance autonomy with the substance of high-impact, technically challenging work Contribute to infrastructure that shapes the future of AI at a foundational level Potential for ongoing engagement and expanded scope as new projects launch