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

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

• 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

• 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

• 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

• 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