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

Senior C++ Full-Stack Engineer — AI Data & Infrastructure About the Role What if your mastery of C++ could directly shape the infrastructure powering 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 — working on real production code with genuine, measurable impact. This is a fully remote, flexible contract role for a seasoned systems engineer who wants to do meaningful 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 large-scale AI data pipelines and evaluation workflows Develop full-stack tooling and backend services for data annotation, validation, and quality control Improve reliability, performance, and safety across production C++ codebases Identify and resolve bottlenecks and edge cases in data and system behavior — then ship scalable fixes 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 3–5+ years of professional experience writing production-grade C++, with a strong focus on modern standards (C++17 or C++20) Deep systems programming background — you're comfortable with performance optimization, concurrency (threading, atomics), and memory safety (RAII, smart pointers, sanitizers) Full-stack developer with experience across backend services and tooling, not just low-level systems Clear, confident communicator — written and verbal — who can engage effectively 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 systems, data quality pipelines, or evaluation infrastructur