Lead Backend Engineer - AI Tooling

Lead Backend Engineer — AI Tooling About The Role What if your Python expertise could directly shape the infrastructure powering next-generation AI? We're looking for a senior backend engineer to build the data pipelines, annotation tooling, and evaluation systems that leading AI labs depend on to train and improve their models. This is a fully remote, flexible contract role for an experienced engineer who wants meaningful, high-impact work — not just another maintenance ticket queue. Organization: AlignerrType: Hourly ContractLocation: RemoteCommitment: 20–40 hours/week What You'll Do Design, build, and optimize high-performance Python systems supporting AI data pipelines and evaluation workflowsDevelop backend services and full-stack tooling for large-scale data annotation, validation, and quality controlArchitect robust APIs (REST/GraphQL), design database schemas, and implement authentication and authorization flowsImprove reliability, performance, and safety across existing Python codebasesCollaborate with data, research, and engineering teams to support model training and evaluation workflowsIdentify bottlenecks and edge cases in data and system behavior, then implement scalable, production-ready fixesLead synchronous code reviews and system design sessions with cross-functional teams Who You Are Native or fluent English speaker with clear written and verbal communication skills5+ years of professional experience writing production Python backend servicesFull-stack developer with a strong systems programming backgroundDeep familiarity with modern web frameworks and strict type enforcement patternsExperienced architecting APIs, designing schemas, and building secure auth systemsAble to commit 20–40 hours per week reliablySelf-directed and comfortable operating with autonomy in a remote environment Nice to Have Prior experience with data annotation platforms, data quality systems, or evaluation pipelinesFamiliarity with AI/ML workflows, model training, or benchmarking infrastructureExperience with distributed systems or developer toolingBackground working with or alongside AI research teams Why Join Us Work on real production systems at the frontier of AI development alongside leading research labsFully remote and flexible — structure your hours around your lifeFreelance autonomy with the substance of genuinely impactful engineering workCollaborate with sharp, mission-driven teams working on problems that actually matterPotential for ongoing work and expanded engagement as projects grow