Software Engineer (C#) - Internal Tooling

Alignerr Corp.; Denver (CO); Remote; USD 83,000 - 131,000; Full time

Job summary

Alignerr is seeking a Software Engineer (C#) to build internal tooling and AI infrastructure. You will design, implement, and optimize high-performance C# systems that power data annotation pipelines, evaluation tooling, and quality-control tooling.

This is a fully remote hourly contract (20–40 hours/week). You will collaborate with data scientists, researchers, and other engineers to scale AI workflows, benchmarking, and model evaluation.

Qualifications

• 3–5+ years of production-grade C# experience.
• Strong systems programming fundamentals.
• Experience with data pipelines and AI workflows.

Responsibilities

• Design, build, and optimize high-performance C# systems for data pipelines and evaluation workflows.
• Develop full-stack tooling and backend services for data annotation, validation, and quality control.
• Improve reliability, performance, and safety of C# codebases.
• Collaborate with data, research, and engineering teams to support model training and evaluation workflows.
• Identify bottlenecks and scale-edge cases with robust solutions.
• Participate in design reviews and architecture decisions.
• Build benchmarking and performance evaluation harnesses.

Skills

C# production

Full-stack basics

Python interop

Benchmarking harnesses

English fluency

Weekly commitment

Job description

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

What if your C# expertise could directly shape the infrastructure powering the next generation of AI? We're looking for experienced full-stack C# engineers to build and improve the systems that leading AI labs depend on — from data annotation pipelines to evaluation harnesses and quality control tooling.

This is a fully remote contract role with flexible commitment. You'll work on real production systems 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 and resolve bottlenecks and edge cases in data and system behavior with scalable solutions
• Participate in synchronous design reviews to iterate on architecture and implementation decisions
• Build and maintain robust benchmarking and performance evaluation harnesses

Who You Are

• 3–5+ years of professional experience writing production-grade C#
• Strong full-stack developer background with solid systems programming fundamentals
• Expertise in interoperability scenarios — such as invoking Python ML models from .NET or wrapping native libraries
• Experienced designing robust harnesses for benchmarking and evaluating system performance
• Native or fluent English speaker with clear written and verbal communication skills
• 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 working with or alongside research teams in a fast-moving environment

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 technical work
• Build systems that directly influence how next-generation AI models are trained and evaluated
• Potential for ongoing work and contract extension as new projects launch