Backend Developer - AI Data Services

Backend Developer — AI Data ServicesAbout The RoleWhat if your C# expertise could directly shape the infrastructure powering the next generation of AI? We're looking for a senior-level full-stack engineer to design and build 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 flexible hours. You'll work on real production systems — not toy projects — alongside data, research, and engineering teams at the forefront of AI development.Organization: AlignerrType: Hourly ContractLocation: RemoteCommitment: 20–40 hours/weekWhat You'll DoDesign, build, and optimize high-performance C# systems supporting large-scale AI data pipelines and evaluation workflowsDevelop full-stack backend tooling and services for data annotation, validation, and quality controlImprove the reliability, performance, and safety of existing C# codebasesCollaborate with research and engineering teams to support model training and evaluation infrastructureIdentify bottlenecks and edge cases across data and system behavior, then implement scalable, production-ready fixesParticipate in synchronous design reviews to iterate on architecture and implementation decisionsWho You AreNative or fluent English speaker with clear written and verbal communication skillsExperienced full-stack developer with a strong systems programming background5+ years of professional experience writing production-grade C#Skilled in data modeling and database access using ORM frameworks or micro-ORMs for high-performance SQL interactionsProven experience building secure, well-documented endpoints for data access and manipulationAble to commit reliably to 20–40 hours per weekNice to HavePrior experience with data annotation, data quality systems, or evaluation pipelinesFamiliarity with AI/ML workflows, model training, or benchmarking infrastructureExperience with distributed systems or developer toolingWhy Join UsWork on cutting-edge AI infrastructure projects alongside leading research labsFully remote and flexible — work when and where it suits youFreelance autonomy with the structure and substance of high-impact, meaningful workMake a direct, tangible contribution to the systems that shape how AI learns and improvesPotential for ongoing work and contract extension as new projects launch