Principal Systems Engineer (C++) - AI Infrastructure

Principal Systems Engineer (C++) — AI Infrastructure About the Role What if your deep C++ expertise could directly shape the infrastructure powering the world's most advanced AI systems? We're looking for a seasoned C++ Systems Engineer to design and build high-performance pipelines, annotation tooling, and evaluation infrastructure used by leading AI labs at the frontier of model development. This is a fully remote, flexible contract role for engineers who thrive on complex systems problems and want their work to matter at scale. 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 large-scale AI data pipelines and evaluation workflows Develop full-stack tooling and backend services for data annotation, validation, and quality control at scale Improve reliability, performance, and safety across existing production C++ codebases Identify bottlenecks and edge cases in data and system behavior, and implement robust, scalable solutions Collaborate with data, research, and engineering teams to support model training and evaluation workflows Participate in synchronous design reviews to iterate on architecture and implementation decisions Who You Are Native or fluent English speaker with clear written and verbal communication skills 5+ years of professional experience writing production C++ for large-scale systems Strong full-stack development background with deep systems programming expertise Advanced knowledge of build system architecture and package management strategies Experienced designing reliable, production-grade systems with rigorous error handling Proficient with memory sanitizers and tooling to ensure memory safety Able to commit 20–40 hours per week consistently Nice to Have Prior experience with data annotation, data quality, or evaluation systems Familiarity with AI/ML workflows, model training, or benchmarking pipelines Experience wi