Software Engineer (C#) - Internal Tooling

Software Engineer (C#) — Internal Tooling (AI Infrastructure) About the Role What if your C# skills could directly shape the systems powering some of the most advanced AI models in the world? We're looking for a Senior C# Full-Stack Engineer to build and optimize the data pipelines, annotation tooling, and evaluation infrastructure that leading AI labs depend on every day. This is a fully remote contract role with flexible hours. You'll work on real production systems — not toy projects — alongside data, research, and engineering teams pushing 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 large-scale AI data pipelines and evaluation workflows Develop full-stack tooling and backend services for 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 Identify and resolve bottlenecks and edge cases in data and system behavior with scalable, well-reasoned solutions 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 3–5+ years of professional experience writing production-grade C# Experienced with interoperability scenarios — such as invoking Python ML models from .NET or wrapping native libraries Proven ability to design robust benchmarking and evaluation harnesses Able to commit 20–40 hours per week reliably 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