C++ Developer — Internal Tooling & Optimization (AI Training) About The Role What if your C++ expertise could directly shape the infrastructure powering the next generation of AI? We're looking for senior-level C++ engineers to design build and optimize the high-performance systems that leading AI labs depend on — from data pipelines and annotation tooling to evaluation infrastructure that runs at scale. This is a fully remote flexible contract role. If you're a systems-minded engineer who loves squeezing performance out of complex codebases and building tooling that other engineers rely on this is the work for you. 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 Profile and debug existing C++ codebases to identify bottlenecks and implement scalable reliable fixes Embed scripting languages within C++ applications to create flexible extensible tooling Collaborate with data research and engineering teams to support model training and evaluation workflows Identify edge cases in data and system behavior and drive systematic improvements 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++ Full-stack developer with a strong systems programming background Experienced profiling code and resolving performance bottlenecks in data-intensive environments Comfortable embedding scripting languages (e.g. Python Lua) within C++ applications Clear and precise written and verbal communicator — you can explain technical decisions concisely Native or fluent English speaker Able to commit 20–40 hours per week with reliability and consistency Nice to Have Prior experience with data annotation data quality pipelines or AI evaluation systems Familiarity with AI/ML workflows model training infrastructure or benchmarking pipelines Experience with distributed systems or developer tooling at scale Background in performance engineering or low-latency systems Why Join Us Work directly on production systems used by leading AI research labs Fully remote and async-friendly — work from wherever you're most productive Freelance autonomy with the structure of meaningful high-impact technical work Contribute to infrastructure that shapes the future of AI development Potential for ongoing work and contract extension as projects grow and evolve