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

About The Role What if your systems programming expertise could directly shape the infrastructure powering the next generation of AI? We’re looking for Senior C++ Engineers to build, optimize, and scale the data pipelines, annotation tooling, and evaluation systems that leading AI labs depend on to train and improve frontier models. This is a fully remote, flexible contract role for seasoned engineers who thrive on high-performance systems work and want their contributions to have real, measurable impact on cutting‑edge 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 production C++ codebases. Identify bottlenecks and edge cases in data and system behavior, and implement scalable, robust fixes. Collaborate with data, research, and engineering teams to support model training and evaluation workflows. Participate in synchronous design reviews to iterate on system architecture and implementation decisions. Who You Are Full‑stack developer with a strong systems programming background and deep C++ expertise. 3–5+ years of professional experience writing production C++, with a focus on modern standards (C++17 or C++20). Solid command of 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 — able to commit 20–40 hours per week and deliver quality work independently. Sharp eye for edge cases, system behavior, and long‑term scalability. Nice to Have Prior experience with data annotation, data quality pipelines, or evaluation systems. Familiarity with AI/ML workflows, model training, or benchmarking infrastructure. Experience building distributed systems or developer tooling at scale. Why Join Us Work on real production systems supporting some of the world's leading AI research labs. Fully remote and flexible — structure your hours around your life. Freelance autonomy with the substance of high‑impact, technically challenging work. Contribute directly to infrastructure that shapes how next‑generation AI models are built and evaluated. Potential for ongoing work and contract extension as projects grow and expand. #J-18808-Ljbffr Alignerr