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Senior Backend Engineer (C#) - AI Data Platform
Remote (Global)
$50 – $75/hr
June 26, 2026
Job description
Senior Backend Engineer (C#) — AI Data Platform
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 Backend Engineer to design and build the high-performance data pipelines, annotation tooling, and evaluation systems that leading AI labs depend on to train and improve their models.
This is a fully remote contract role with flexible hours. You'll be working 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 backend systems in C# supporting large-scale AI data pipelines and evaluation workflows
- Develop backend services and tooling for data annotation, validation, and quality control at scale
- Build and maintain RESTful APIs and RPC services for reliable inter-service communication
- Integrate with cloud-native data services and orchestrate workflows via message bus architectures
- Identify bottlenecks, edge cases, and reliability issues across existing codebases — then implement scalable fixes
- Collaborate with research and engineering teams to support model training, benchmarking, and evaluation workflows
- Participate in synchronous design reviews and iterate on system architecture decisions
Who You Are
- 5+ years of professional experience building scalable backend services in C#
- Deep command of modern C# frameworks for RESTful APIs and RPC-based inter-service communication
- Experienced integrating with cloud-native data services and message bus architectures
- Systems-level thinker who can identify performance issues and architect clean, scalable solutions
- Clear, concise written and verbal communicator — comfortable working with cross-functional teams
- 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 evaluation pipelines
- Familiarity with AI/ML workflows, model training, or benchmarking infrastructure
- Experience with distributed systems design or developer tooling
- Full-stack background with frontend exposure alongside a strong backend foundation
Why Join Us
- Work directly on cutting-edge AI projects alongside leading research labs
- Fully remote and flexible — work from wherever you do your best work
- Freelance autonomy with the structure of meaningful, high-impact engineering work
- Contribute to infrastructure that shapes how next-generation AI systems are built and evaluated
- Potential for ongoing work and contract extension as new projects launch
Apply now
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About Vercel: Vercel is the agentic infrastructure company. We free people and agents to ship what’s next. For more than a decade, Vercel has shaped how the web is built.
About Vercel: Vercel is the agentic infrastructure company. We free people and agents to ship what’s next. For more than a decade, Vercel has shaped how the web is built.
AI Engineer (Contract) Please note that this is a contract role providing services to Microsoft through external staffing partners of Allegis Global Solutions. If you are selected for this role, you will be employed by AGS and will not be an employee of Microsoft.