Senior Python Full-Stack Engineer — AI Data & Infrastructure

About The Role What if your Python expertise could directly shape the infrastructure behind the world's most advanced AI systems? We're looking for a Senior Python 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 with meaningful technical challenges, flexible hours, and the opportunity to work on production systems that sit at the frontier of AI development. Organization: AlignerrType: Hourly ContractLocation: RemoteCommitment: 20–40 hours/week What You'll Do Design, build, and optimize high-performance Python systems supporting large-scale AI data pipelines and evaluation workflowsDevelop full-stack tooling and backend services for data annotation, validation, and quality control at scaleImprove the reliability, performance, and safety of existing Python codebasesCollaborate with data, research, and engineering teams to support model training and evaluation infrastructureIdentify bottlenecks and edge cases in data and system behavior — then implement scalable, production-ready fixesParticipate 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 skillsFull-stack developer with a strong systems programming background5+ years of professional experience writing production-grade PythonDeep understanding of performance optimization and concurrency — asyncio, multiprocessing, threadingComfortable with type safety tooling such as Pydantic and mypyExperienced building robust backend services (FastAPI, Django, or similar) or scalable data pipelinesAble to commit 20–40 hours per week with consistency Nice to Have Prior experience with data annotation, data quality pipelines, or evaluation systemsFamiliarity with AI/ML workflows, model training, or benchmarking infrastructureExperience with distributed systems or developer toolingBackground working alongside research or applied ML teams Why Join Us Work directly on production AI infrastructure used by leading research labsFully remote and flexible — work from anywhere on a schedule that suits youFreelance autonomy paired with technically meaningful, high-impact workCollaborate with sharp engineers and researchers at the cutting edge of AIPotential for ongoing work and contract extension as projects evolve and expand