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

Work arrangement
Yes