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