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Posted May 16, 2026

Senior C++ Full-Stack Engineer — AI Data & Infrastructure

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About The Role What if your C++ skills could directly shape the infrastructure behind the world's most advanced AI systems? We're looking for a Senior C++ Full-Stack Engineer to build and optimize the data pipelines, annotation tooling, and evaluation systems that leading AI labs depend on to train and improve next-generation models. This is a fully remote contract role working on real production systems — not toy projects. You'll be embedded alongside data, research, and engineering teams doing high-impact work 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 C++ systems supporting AI data pipelines and evaluation workflows • Develop full-stack tooling and backend services for large-scale data annotation, validation, and quality control • Improve reliability, performance, and safety across existing C++ codebases — from concurrency bottlenecks to memory safety issues • Collaborate closely with data, research, and engineering teams to support model training and evaluation workflows • Identify edge cases and systemic bottlenecks in data and system behavior, then implement scalable, production-ready fixes • Participate in synchronous design reviews to iterate on architecture and implementation decisions Who You Are • Full-stack developer with a strong systems programming foundation and a bias for clean, performant code • 3–5+ years of professional experience writing production C++, with fluency in modern standards (C++17 or C++20) • Deep understanding of systems programming fundamentals — performance optimization, concurrency (threading, atomics), and memory safety (RAII, smart pointers, sanitizers) • Native or fluent English speaker with clear written and verbal communication skills • Self-directed and reliable with the ability to commit 20–40 hours per week Nice to Have • Prior experience with data annotation, data quality systems, or evaluation pipelines • Familiarity with AI/ML workflows, model training, or benchmarking infrastructure • Experience with distributed systems or developer tooling at scale Why Join Us • Work on cutting-edge AI infrastructure alongside leading research labs — your code will matter • Fully remote and flexible — work where and how you do your best work • Freelance autonomy with meaningful, technically challenging work • Direct impact on the data systems and tooling that shape how next-generation AI models are built • Potential for ongoing work and contract extension as new projects launch Apply tot his job Apply To this Job