Senior Backend Engineer (C#) - AI Data Platform

Posted 8 days 1 hour ago by Labelbox

Permanent
Part Time
Other
Not Specified, United Kingdom
Job Description
About the Job

Alignerr connects top technical experts with leading AI labs to build, evaluate, and improve next-generation models. We work on real production systems and high-impact research workflows across data, tooling, and infrastructure.

Position

Senior C# Full-Stack Engineer - AI Data & Infrastructure

Type: Contract, Remote Commitment: 20-40 hours/week Compensation: Competitive, hourly (based on experience)

Role Responsibilities
  • Design, build, and optimize high-performance systems in C# 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 fixes
  • Participate in synchronous reviews to iterate on system design and implementation decisions
Qualifications Must-Have
  • Native or fluent English speaker
  • Full-stack developer experience with a strong systems programming background
  • 5+ years of professional experience building scalable backend services in C#.
  • Mastery of modern frameworks for building RESTful APIs and RPC services for inter-service communication.
  • Experience integrating with cloud-native data services and orchestrating workflows via message bus architectures.
  • Clear written and verbal communication skills.
  • Ability to commit 20-40 hours per week.
Preferred
  • 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
Application Process
  • Submit your resume
  • Complete a short technical screening
  • Project matching and onboarding

$50 - $75 an hour