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Software Engineer (C#) - Internal Tooling

$50-75/hrRemoteFreelanceCODING

About the Role

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

This isn't toy work or proof-of-concept territory. You'll be writing production code that sits at the heart of real AI training and evaluation workflows — the kind of systems that determine how models learn, improve, and get measured.

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

What You'll Do

  • Design and build high-performance C# systems that support large-scale AI data pipelines and evaluation workflows
  • Develop full-stack tooling and backend services for data annotation, validation, and quality control at scale
  • Improve reliability, performance, and correctness across existing C# codebases
  • Build robust benchmarking and evaluation harnesses to measure system behavior
  • Implement interoperability solutions — such as invoking Python ML models from .NET or wrapping native libraries
  • Identify bottlenecks and edge cases, then ship scalable, well-reasoned fixes
  • Collaborate with data, research, and engineering teams across model training and evaluation workflows
  • Participate in synchronous design reviews to iterate on architecture and implementation decisions

Who You Are

  • 3–5+ years of professional experience writing production-grade C#
  • Strong full-stack developer with a solid systems programming foundation
  • Experienced in interoperability scenarios — calling Python ML models from .NET, wrapping native libraries, bridging ecosystems
  • Proven track record designing benchmarking harnesses and performance evaluation systems
  • Clear, precise written and verbal communicator — you can explain technical decisions to mixed audiences
  • 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 pipelines, or evaluation systems
  • Familiarity with AI/ML workflows, model training, or benchmarking infrastructure
  • Experience with distributed systems or developer tooling
  • Background working in fast-moving research or AI-adjacent engineering environments

Why Join Us

  • Work on real production systems alongside top AI research labs — not toy demos
  • Fully remote and flexible — structure your hours around your best work
  • Freelance autonomy with the substance of meaningful, high-stakes engineering
  • Make a tangible impact on the infrastructure that shapes how next-generation AI models are built and evaluated
  • Potential for ongoing work and contract extension as projects grow