Lead Backend Engineer - AI Tooling

Lead Backend Engineer — AI ToolingAbout The RoleWhat if your Python expertise could directly shape the infrastructure powering next-generation AI models? We're looking for a Senior Backend Engineer to design and build the data pipelines, annotation systems, and evaluation tooling that leading AI labs depend on to train and improve their most important models.This is a fully remote contract role with flexible hours — real, high-impact engineering work on production systems at the frontier of AI development.Organization: AlignerrType: Hourly ContractLocation: RemoteCommitment: 20–40 hours/weekWhat You'll DoDesign, 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, and implement scalable solutionsLead synchronous code reviews and contribute to system design decisionsWho You AreNative or fluent English speaker with strong written and verbal communication skillsExperienced full-stack developer with a strong systems programming background5+ years of professional experience writing production Python backend servicesDeep familiarity with modern web frameworks and strict type enforcement patternsComfortable leading code reviews and driving system design discussionsAble to commit 20–40 hours per week with reliable availabilityNice to HavePrior experience with data annotation, data quality, or evaluation systemsFamiliarity with AI/ML workflows, model training, or benchmarking pipelinesExperience with distributed systems or developer toolingBackground working directly with or alongside AI research teamsWhy Join UsWork on real production systems used by leading AI labs — not toy projectsFully remote and flexible — structure your hours around your lifeFreelance autonomy with the depth and challenge of high-stakes engineering workMake a tangible impact on AI systems that are shaping the future of technologyPotential for ongoing work and contract extension as new projects launch