C# Quality Assurance Lead — .NET Code Review

About OpenTrain

OpenTrain is the #1 platform for finding and building careers in AI training and data labeling. We help people discover projects, build a unified AI training portfolio, and grow durable freelance careers working on the human side of AI.

Our work sits at the intersection of engineering and human judgment: contributors shape how models behave by reviewing outputs, annotating data, and teaching systems correct behavior. This role is part of that mission, focused on C# and .NET code quality for AI training.

Why AI training matters — the role in context

AI systems learn from examples and human feedback. Expert reviewers are essential to ensure generated code is correct, secure, maintainable, and follows project rubrics. This role puts you on the front line of shaping how code-writing models behave in real-world .NET scenarios.

• Work directly impacts model quality by evaluating and improving training data and reviewer guidance.
• Flexible, remote-friendly work that supports part-time contracting schedules.

The role — what you'll own

As the C# Quality Assurance Lead you will evaluate AI-generated C# code and trainer QA submissions, enforce rubric adherence, and produce precise written feedback. You will monitor quality, escalate recurring or critical issues, and lead efforts to improve reviewer guidance and processes.

• Review C#/.NET snippets, API examples, debugging responses, tests, architecture explanations, and step-by-step reasoning.
• Identify correctness, runtime behavior, type-safety, async issues, security risks, hallucinated APIs, and incomplete explanations.
• Create and maintain style guides, onboarding materials, calibration tasks, honeypots, trackers, and FAQs.

What you'll do day-to-day

You will balance hands-on code review with contributor support and process work. Expect a mix of reviewing submissions, writing clear feedback, running calibration and onboarding sessions, and iterating on QA artifacts that keep the review team aligned.

• Provide clear, actionable written feedback in English on individual submissions and patterns of failure.
• Answer contributor questions about .NET behavior (async/await, LINQ, DI, EF Core, runtime semantics).
• Run onboarding and training calls for C# contributors and help improve QA workflows and tooling.
• Escalate and document recurring or critical quality issues and propose fixes to rubrics and examples.

Requirements

You must be an expert C#/.NET engineer with proven code-review judgment and experience supporting or leading remote technical contributors. This role requires strong written English and the ability to translate technical findings into crisp reviewer guidance.

• Strong C#/.NET development background (backend engineering, code review, QA, or technical mentoring).
• Deep knowledge of C# syntax, OOP, LINQ, generics, collections, exceptions, async/await, tasks, DI, nullable reference types, records, delegates/events, and .NET runtime behavior.
• Ability to spot incorrect logic, non-executable code, flawed async usage, weak type safety, security risks, hallucinated APIs, and incomplete explanations.
• Experience evaluating AI-generated code or rubric-based code review is highly relevant.
• Strong written English communication and experience leading or supporting remote teams of trainers, reviewers, engineers, or QAs.

Helpful familiarity (preferred but not required)

These technologies and tools are commonly encountered in our projects and speed onboarding, but they are not strict requirements unless specified in a given task.

• ASP.NET Core, Entity Framework Core, xUnit/NUnit/MSTest, Visual Studio or Rider, NuGet.
• Cloud and infra basics: Azure, AWS, Docker, CI/CD, logging tools and GitHub workflows.
• Experience with calibration tasks, trackers, Google Sheets/Docs, Discord, and contributor dashboards.

Logistics, pay, and how to apply

This is a contractor, part-time role requiring 20+ hours/week. Candidates must be located in the United States and fluent in English. Compensation is $75 USD per hour.

Typical onboarding includes calibration tasks, documentation review, and training calls. You will work with trackers and contributor communication channels to keep quality high and consistent.

• Employment type: Contractor, Part-time.
• Time commitment: 20+ hours per week.
• Location: United States only (remote).
• Pay: $75 USD / hour.
• Labeling work: Evaluation/rating and RLHF-style reviewer assessments of code outputs.