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

• 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

• 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

• 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

• 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