C++ Backend Engineer - AI Data Platforms

C++ Backend Engineer — AI Data Platforms About The Role What if your expertise in high-performance C++ could directly shape the infrastructure powering the world's most advanced AI systems? We're looking for a Senior C++ Backend Engineer to design, build, and optimize the data pipelines, annotation tooling, and evaluation infrastructure that leading AI labs depend on to train and improve next-generation models. This is a fully remote contract role with flexible hours. If you've spent years writing production C++ and want to do some of the most technically meaningful work of your career — this is it. • 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 backend services and tooling for data annotation, validation, and quality control at scale • Improve reliability, performance, and correctness across existing production C++ codebases • Identify bottlenecks and edge cases in system and data behavior, then implement scalable, maintainable fixes • Collaborate asynchronously with data, research, and engineering teams to support model training and benchmarking 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 • 5+ years of professional experience writing production-grade C++ • Strong background in asynchronous network programming — event loops, RPC frameworks, or similar patterns for high-performance microservices • Experience interfacing with high-throughput databases or message queues • Full-stack development experience with a solid systems programming foundation • Able to commit 20–40 hours per week consistently Nice to Have • Prior experience with data annotation pipelines, data quality systems, or evaluation infrastructure • Familiarity with AI/ML workflows, model training pipelines, or benchmarking systems • Experience building distributed systems or developer tooling • Background working alongside research or ML engineering teams Why Join Us • Work on production systems used by leading AI research labs — real impact, not toy projects • Fully remote and flexible — work from wherever you do your best thinking • Freelance autonomy with the focus and structure of high-stakes engineering work • Collaborate with sharp engineers and researchers on some of the most challenging infrastructure problems in AI today • Potential for ongoing work and contract extension as new projects launch