Software Engineer (C#) - Internal Tooling

Alignerr Corp.; Seattle (WA); Remote; USD 28,000 - 55,000; Part time

Job summary

Alignerr is seeking a senior full-stack C# engineer to build internal tooling and data pipelines powering AI infrastructure. This remote hourly contract role offers 20–40 hours per week and collaboration with data, research, and engineering teams on production AI systems.

You will design, build, and optimize high-performance C# systems, develop tooling for data annotation and quality control, and improve reliability across codebases. Remote work with flexible hours.

Qualifications

• 3–5+ years of professional experience writing production-grade C#.
• Full-stack developer with strong systems programming background.
• Experience with interoperability scenarios—invoking Python ML models from .NET.

Responsibilities

• Design, build, and optimize high-performance C# systems for AI data pipelines.
• Develop full-stack tooling and backend services for data annotation, validation, and quality control.
• Improve reliability, performance, and safety across existing C# codebases.
• Collaborate with data, research, and engineering teams to support model training and evaluation workflows.
• Identify bottlenecks and implement scalable fixes.

Skills

C# development

Full-stack engineering

Systems programming

Cross-language integration

Tools

Python interop

Job description

Software Engineer (C#) — Internal Tooling (AI Infrastructure)

About The Role

What if your C# skills could directly shape the infrastructure powering next-generation AI systems used by millions of people? We're looking for a senior full-stack C# engineer to build and optimize the internal tooling, data pipelines, and evaluation systems that leading AI labs depend on every day.

This is a fully remote contract role with flexible hours. You'll work on real production systems — not toy projects — alongside data, research, and engineering teams at the frontier of AI development.

• Organization: Alignerr
• Type: Hourly Contract
• Location: Remote
• Commitment: 20–40 hours/week

What You'll Do

• Design, build, and optimize high-performance C# systems supporting AI data pipelines and evaluation workflows
• Develop full-stack tooling and backend services for large-scale data annotation, validation, and quality control
• Improve reliability, performance, and safety across existing C# codebases
• Collaborate with data, research, and engineering teams to support model training and evaluation workflows
• Identify bottlenecks and edge cases in data and system behavior, then implement scalable fixes
• Participate in synchronous design reviews to iterate on architecture and implementation decisions

Who You Are

• Native or fluent English speaker with strong written and verbal communication skills
• Full-stack developer with a solid systems programming background
• 3–5+ years of professional experience writing production-grade C#
• Experienced with interoperability scenarios — invoking Python ML models from .NET, wrapping native libraries, or similar cross-language integrations
• Skilled at designing robust harnesses for benchmarking and evaluating system performance
• Able to commit 20–40 hours per week with reliability and consistency

Nice to Have

• Prior experience with data annotation, data quality, or evaluation systems
• Familiarity with AI/ML workflows, model training, or benchmarking pipelines
• Experience with distributed systems or developer tooling
• Background in research infrastructure or high-throughput data processing

Why Join Us

• Work on cutting-edge AI projects alongside leading research labs
• Fully remote and flexible — work when and where it suits you
• Freelance autonomy with the structure of meaningful, high-impact engineering work
• Make a direct, tangible contribution to the infrastructure driving the next generation of AI
• Potential for ongoing work and contract extension as new projects launch