Software Engineer (C#) - Internal Tooling

Alignerr Corp.; New York (NY); Remote; USD 83,000 - 131,000; Part time

Job summary

Alignerr is seeking a Software Engineer (C#) for internal tooling and AI infrastructure. You will design, build, and optimize high-performance C# systems for data pipelines and evaluation workflows, while developing tooling for large-scale data annotation and quality control.

Collaboration with AI researchers and engineers is essential to improve model training and deployment. The role is remote, hourly contract, with 20–40 hours per week, and requires 3–5+ years of production-grade C#

Qualifications

• 3–5+ years of professional experience writing production-grade C# (backend and full-stack responsibilities).
• Experience designing high-performance data pipelines and tooling for AI infrastructure.
• Interoperability work such as invoking Python ML models from .NET or wrapping native libraries is a plus.

Responsibilities

• 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, and implement scalable, production-ready fixes.
• Participate in design reviews and iterate on architecture with senior engineers.

Skills

C# development

Full-stack development

Systems programming

Python interop (Python.NET)

Benchmarking harnesses

Tools

.NET

Job description

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

About The Role

What if your C# expertise could directly shape the infrastructure powering the world's most advanced AI systems? We're looking for experienced C# full-stack engineers to build and optimize the data pipelines, annotation tooling, and evaluation systems that leading AI labs depend on.

• 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, and implement scalable, production-ready fixes
• Participate in synchronous design reviews and iterate on system architecture decisions with senior engineers

Who You Are

• Native or fluent English speaker with clear written and verbal communication skills
• Full-stack developer with a strong systems programming background
• 3–5+ years of professional experience writing production-grade C#
• Experienced in interoperability scenarios — such as invoking Python ML models from .NET or wrapping native libraries
• Skilled at designing robust benchmarking and evaluation harnesses
• Able to commit 20–40 hours per week consistently

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 working directly with or alongside AI research teams

Why Join Us

• Work on cutting-edge AI infrastructure alongside leading research labs
• Fully remote and flexible — work from wherever you do your best engineering
• Freelance autonomy with the structure and consistency of ongoing, meaningful project work
• Tackle genuinely hard technical problems with real-world impact on AI systems at scale
• Potential for ongoing work and contract extension as new projects launch