About OpenTrain

OpenTrain is the #1 platform for finding and building careers in AI training and data labeling. We help freelancers discover projects, build a unified AI training portfolio, and grow a durable freelance career by consolidating specialized work and proof-of-work in one place.

About AI training work

AI training (data labeling and evaluation) is the human side of building modern AI systems. Contributors annotate, evaluate, and correct model outputs so models learn to behave correctly; for code-focused projects that often means reviewing generated code, rating answers, and producing model solutions.

This role connects deep C and systems expertise with cutting-edge model evaluation: you will directly influence how AI tools reason about low-level programming, memory, concurrency, and performance.

The role

OpenTrain is hiring a C AI Code Review Engineer to evaluate AI-generated C code, systems designs, and technical explanations. You will assess correctness, safety, memory handling, concurrency, and performance; identify undefined behavior and subtle logic errors; and write reference implementations and clear step-by-step reasoning that demonstrate correct approaches.

Work will include rating and comparing multiple model responses, fact-checking technical claims, and producing high-quality model solutions and explanations. Typical label types for assignments include evaluation/rating, text generation (explanations), and programming/code verification.

What you'll do

• Review AI-generated C code, technical explanations, and low-level designs for correctness and safety.
• Identify memory-management bugs, undefined behavior, concurrency issues, and performance regressions.
• Write reference implementations, testable examples, and step-by-step reasoning for complex problems.
• Compare and rate multiple model responses on correctness, clarity, and reasoning quality.
• Fact-check technical information and propose corrections that improve model integrity and safety.

Requirements

• Expert-level C programming knowledge, especially pointers, memory management, undefined behavior, and debugging.
• Background in systems programming, embedded development, concurrency, operating systems, and performance optimization.
• Experience with build systems, compilers, linkers, and low-level debugging tools.
• Strong code-review habits focused on maintainability and safety, and the ability to write clear technical explanations in English.
• Prior experience evaluating AI-generated technical content or working on AI data training is a strong plus.

Helpful background

• Familiarity with version control, CI/CD workflows, automated testing, and reproducible builds for C projects.
• Experience with hardware interaction and performance-critical software (embedded, drivers, or real-time systems).
• Methodical, detail-oriented approach to evaluating low-level technical work and documenting findings.

Schedule, pay, and logistics

This is a remote contractor role for part-time work. Expect 20+ hours per week with independent, project-driven assignments. OpenTrain is the hiring and contracting organization for this role.

• Pay: $65.00 USD per hour (hourly contractor rate).
• Time requirement: 20+ hours/week; part-time contractor work.
• Languages: English required.
• Location: Open to applicants located in VN, TL, TH, SG, PK, PH, NP, MY, LK, KH, ID, BT, BD, IN, BR, DE, US (work is not worldwide beyond these countries).

How it works and who should apply

Apply through your OpenTrain profile. Strong candidates are mid‑to‑senior systems engineers or embedded/C specialists who enjoy precise technical evaluation and clear written explanations. You do not need prior AI industry experience to apply, but experience reviewing AI-generated outputs is a plus.

Successful reviewers follow project guidelines closely, produce reproducible reference code and clear reasoning, and consistently deliver high-quality, well-documented feedback that helps models improve.