Software Engineer (C#) - Internal Tooling
Software Engineer (C#) — Internal Tooling (AI Infrastructure)About The RoleWhat if your C# expertise could directly shape the infrastructure powering the next generation of AI? We're looking for experienced full-stack C# engineers to build and improve the systems that leading AI labs depend on — from data annotation pipelines to evaluation harnesses and quality control tooling.This is a fully remote contract role with flexible commitment. You'll work on real production systems alongside data, research, and engineering teams at the frontier of AI development.Organization: AlignerrType: Hourly ContractLocation: RemoteCommitment: 20–40 hours/weekWhat You'll DoDesign, build, and optimize high-performance C# systems supporting AI data pipelines and evaluation workflowsDevelop full-stack tooling and backend services for large-scale data annotation, validation, and quality controlImprove reliability, performance, and safety across existing C# codebasesCollaborate with data, research, and engineering teams to support model training and evaluation workflowsIdentify and resolve bottlenecks and edge cases in data and system behavior with scalable solutionsParticipate in synchronous design reviews to iterate on architecture and implementation decisionsBuild and maintain robust benchmarking and performance evaluation harnessesWho You Are3–5+ years of professional experience writing production-grade C#Strong full-stack developer background with solid systems programming fundamentalsExpertise in interoperability scenarios — such as invoking Python ML models from .NET or wrapping native librariesExperienced designing robust harnesses for benchmarking and evaluating system performanceNative or fluent English speaker with clear written and verbal communication skillsAble to commit 20–40 hours per week with reliability and consistencyNice to HavePrior experience with data annotation, data quality, or evaluation systemsFamiliarity with AI/ML workflows, model training, or benchmarking pipelinesExperience with distributed systems or developer toolingBackground working with or alongside research teams in a fast-moving environmentWhy Join UsWork on cutting-edge AI projects alongside leading research labsFully remote and flexible — work when and where it suits youFreelance autonomy with the structure of meaningful, high-impact technical workBuild systems that directly influence how next-generation AI models are trained and evaluatedPotential for ongoing work and contract extension as new projects launch