Backend Developer — AI Data Services About The Role What if your C# expertise could directly shape the infrastructure powering the next generation of 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 to train and improve their models. This is a fully remote contract role with real technical depth — you'll work on production systems that matter, alongside data, research, and engineering teams 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 evaluation workflows

Develop full-stack tooling and backend services 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 workflows

Identify bottlenecks and edge cases in data and system behavior, and implement scalable 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#

Strong skills in data modeling and database access using ORM frameworks or micro-ORMs for high-performance SQL interactions

Experienced building secure, well-documented endpoints for data access and manipulation

Able to commit 20–40 hours per week with reliability and consistency Nice to Have Prior experience with data annotation, data quality, or evaluation systems

Familiarity with AI/ML workflows, model training, or benchmarking pipelines

Experience with distributed systems or developer tooling Why Join Us Work directly with leading AI labs on real production infrastructure — not toy projects

Fully remote and async-friendly — work from wherever you do your best thinking

Freelance autonomy with the structure of meaningful, ongoing technical work

Contribute to systems that have a measurable impact on how next-generation AI is built and evaluated

Potential for extended engagement as new projects and infrastructure needs grow

📌 Backend Developer - AI Data Services (México)
🏢 Alignerr
📍 México