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 world's most advanced AI systems? We're looking for experienced C# full-stack engineers to build and optimize the data pipelines, annotation tooling, and evaluation systems that leading AI labs depend on.This is a fully remote contract role with meaningful technical scope — real production systems, high-impact workflows, and the kind of engineering problems that actually stretch your skills.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 bottlenecks and edge cases in data and system behavior, and implement scalable, production-ready fixesParticipate in synchronous design reviews and iterate on system architecture decisions with senior engineersWho You AreNative or fluent English speaker with clear written and verbal communication skillsFull-stack developer with a strong systems programming background3–5+ years of professional experience writing production-grade C#Experienced in interoperability scenarios — such as invoking Python ML models from .NET or wrapping native librariesSkilled at designing robust benchmarking and evaluation harnessesAble to commit 20–40 hours per week consistentlyNice 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 directly with or alongside AI research teamsWhy Join UsWork on cutting-edge AI infrastructure alongside leading research labsFully remote and flexible — work from wherever you do your best engineeringFreelance autonomy with the structure and consistency of ongoing, meaningful project workTackle genuinely hard technical problems with real-world impact on AI systems at scalePotential for ongoing work and contract extension as new projects launch