Lead Backend Engineer - AI Tooling

Lead Backend Engineer — AI Tooling About The Role What if your Python expertise could directly shape the infrastructure that powers the world’s most advanced AI systems? We’re looking for a senior backend engineer to build and lead the data pipelines, annotation tooling, and evaluation infrastructure that leading AI labs depend on to train and improve their models.

This is a fully remote contract role working on real production systems at the cutting edge of AI development. If you’re a senior engineer who wants meaningful, high-impact work — not another CRUD app — 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 Python systems supporting AI data pipelines and model evaluation workflows
• Develop backend services and full-stack tooling for large-scale data annotation, validation, and quality control
• Architect robust APIs (REST/GraphQL), design database schemas, and implement authentication and authorization flows
• Improve reliability, performance, and safety across existing Python codebases
• Identify bottlenecks and edge cases in data and system behavior, then implement scalable, production-ready fixes
• Collaborate with data, research, and engineering teams across model training and evaluation workflows
• Lead synchronous design and code reviews — driving decisions that shape the architecture of critical AI systems

Who You Are

• Native or fluent English speaker with strong written and verbal communication skills
• Full-stack developer with a deep systems programming background and 5+ years writing production Python backend services
• Fluent in modern Python web frameworks with strict type enforcement patterns
• Experienced architecting scalable APIs, data schemas, and auth systems in production environments
• A natural leader in code reviews and system design sessions — you can articulate decisions clearly and bring others along
• Able to commit 20–40 hours per week on a reliable, ongoing basis

Nice to Have

• Prior experience with data annotation, data quality pipelines, or AI evaluation systems
• Familiarity with AI/ML workflows, model training, or benchmarking infrastructure
• Experience with distributed systems, developer tooling, or platform engineering

Why Join Us

• Work directly with leading AI labs on systems that influence next-generation model development
• Fully remote and flexible — work from wherever you do your best work
• Freelance autonomy with the structure and stability of ongoing, project-based engagement
• Make a real, measurable impact on the infrastructure behind some of the most advanced AI in the world
• Potential for extended engagement and expanded scope as projects grow