Senior Backend Engineer (C#) - AI Data Platform
About this role
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 Backend Engineer to design and build the high-performance 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 be working on real production systems — not toy projects — 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 backend systems in C supporting large-scale AI data pipelines and evaluation workflows - Develop backend services and tooling for data annotation, validation, and quality control at scale - Build and maintain RESTful APIs and RPC services for reliable inter-service communication - Integrate with cloud-native data services and orchestrate workflows via message bus architectures - Identify bottlenecks, edge cases, and reliability issues across existing codebases — then implement scalable fixes - Collaborate with research and engineering teams to support model training, benchmarking, and evaluation workflows - Participate in synchronous design reviews and iterate on system architecture decisions Who You Are - 5+ years of professional experience building scalable backend services in C - Deep command of modern C frameworks for RESTful APIs and RPC-based inter-service communication - Experienced integrating with cloud-native data services and message bus architectures - Systems-level thinker who can identify performance issues and architect clean, scalable solutions - Clear, concise written and verbal communicator — comfortable working with cross-functional teams - Native or fluent English speaker - Able to commit 20–40 hours per week consistently Nice to Have - Prior experience with data annotation platforms, data quality systems, or evaluation pipelines - Familiarity with AI/ML workflows, model training, or benchmarking infrastructure - Experience with distributed systems design or developer tooling - Full-stack background with frontend exposure alongside a strong backend foundation Why Join Us - Work directly on cutting-edge AI projects alongside leading research labs - Fully remote and flexible — work from wherever you do your best work - Freelance autonomy with the structure of meaningful, high-impact engineering work - Contribute to infrastructure that shapes how next-generation AI systems are built and evaluated - Potential for ongoing work and contract extension as new projects launch
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