Backend Developer - Data Annotation Systems

Alignerr Corp.; Seattle (WA); Remote; USD 83,000 - 165,000; Part time

Job summary

Alignerr invites a Senior Python Full-Stack Engineer to join its data annotation and evaluation tooling for AI training. This role focuses on production-grade Python systems, performance, and scalable pipelines in a remote contract arrangement.

You'll build data pipelines, annotation tooling, and background-job systems, collaborating with researchers and engineers across time zones. 20–40 hours weekly, hourly contract basis.

Qualifications

• 3–5+ years of production-grade Python experience.
• Strong full-stack and systems programming background.
• Experience with asynchronous task queues and background jobs.
• Ability to optimize high-throughput databases and use WebSockets.

Responsibilities

• Design, build, and optimize high-performance Python systems for data pipelines.
• Develop full-stack tooling and backend services for annotation, validation, and QC.
• Build and maintain asynchronous task queues for long-running jobs.
• Optimize queries for high read/write workloads; serve data via real-time protocols.
• Improve reliability and performance of production Python codebases.
• Collaborate with data scientists, researchers, and engineers for training/eval workflows.
• Identify bottlenecks and implement scalable fixes.
• Participate in design reviews to drive architecture decisions.

Skills

Python development

Full-stack development

Asynchronous task queues

Database optimization

WebSockets

Technical communication

English fluency

Part-time availability

Tools

Python

Async frameworks

WebSockets

Databases

Redis

Job description

Backend Developer — Data Annotation Systems (AI Training)

About The Role

What if your Python expertise could directly shape the infrastructure that trains the world's most advanced AI models? 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 every day.

This is a fully remote, flexible contract role for a seasoned engineer who wants to work on real production systems — not toy projects — alongside top-tier research and engineering teams.

• 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 large-scale AI data pipelines and model evaluation workflows
• Develop full-stack tooling and backend services for data annotation, validation, and quality control at scale
• Build and maintain asynchronous task queues to handle long-running background jobs reliably
• Optimize database queries for high-read/write workloads and serve data via real-time protocols including WebSockets
• Improve reliability, performance, and safety across existing production Python codebases
• Collaborate with data scientists, researchers, and engineers to support model training and evaluation workflows
• Identify bottlenecks and edge cases across data systems and implement scalable, production-grade fixes
• Participate in synchronous design and code reviews to drive sound architectural decisions

Who You Are

• 3–5+ years of professional experience writing production-grade Python
• Strong full-stack developer with a solid systems programming background
• Experienced building asynchronous task queues and background job systems
• Proficient in optimizing database queries for high-throughput applications
• Comfortable serving and consuming real-time data via WebSockets or similar protocols
• Clear, precise written and verbal communicator — you can articulate technical decisions well
• Native or fluent English speaker
• Able to commit 20–40 hours per week consistently

Nice to Have

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

Why Join Us

• Work on cutting-edge AI infrastructure alongside leading research labs — this is real, high-stakes work
• Fully remote and async-friendly — work from wherever you do your best thinking
• Freelance autonomy with the structure and consistency of meaningful, ongoing project work
• Make a direct, tangible impact on how next-generation AI models are built, trained, and evaluated
• Potential for ongoing work and contract extension as new projects and partnerships launch