Senior C Code Reviewer

About OpenTrain

OpenTrain AI is the hiring and contracting organization for this role and the #1 platform for finding and building careers in AI training and data labeling. OpenTrain helps people discover cutting-edge projects, build a profile, and apply in minutes. Creating an account is free.

• Contractor engagement with part-time availability
• Open to contributors in India, the Philippines, and Vietnam
• English-language work

About AI Training and Code Evaluation

AI training is the human work behind modern artificial intelligence. Contributors prepare and review examples that help AI systems learn, including evaluating generated code, checking technical accuracy, and providing feedback that improves future model behavior.

In this role, your software engineering expertise will help safeguard the quality of data used to train next-generation AI models.

• Work on cutting-edge AI development
• Use expert judgment to improve model-generated programming content
• Contribute to flexible, part-time work in a fast-growing technology field

The Role

OpenTrain is seeking a Senior C Code Reviewer with at least seven years of professional experience in modern C, QA, or dedicated code review. You will audit annotator reviews of AI-generated C code and determine whether each submission satisfies its prompt, works correctly, and meets rigorous quality standards.

The role requires deep knowledge of C11 and C18, advanced memory-management and concurrency expertise, and a security-first mindset. Clear written English is essential. The expected workload is 20+ hours per week at a rate of $24 per hour.

• Pay: $24 USD per hour
• Time requirement: 20+ hours per week
• Engagement: Part-time contractor
• Experience expectation: At least seven years in professional C development, QA, or code review
• Required language: English

What You'll Do

You will validate code reviews by compiling and running C snippets in sandboxed containers. You will test behavior under multiple build flags, verify prompt compliance, and assess implementation quality across functionality, performance, and security.

When an annotator rating is incorrect, you will correct it and provide concise feedback. Every review must align with the project’s quality rubric and help maintain reliable training data.

• Audit annotator reviews of AI-generated C code
• Compile and execute submissions in sandboxed container environments
• Test code under multiple build flags
• Identify undefined behavior, buffer overruns, memory errors, and data races
• Evaluate performance and security best practices
• Correct mis-ratings and provide precise written feedback
• Apply rubric-based scoring and checklist-driven quality controls

Required Qualifications

You should bring advanced C development and review expertise, along with practical experience debugging, testing, profiling, and securing low-level software. Familiarity with modern toolchains and structured review workflows is important for completing consistent, evidence-based evaluations.

• Deep knowledge of modern C, including C11, C18, the standard library, GCC, Clang, CMake, Meson, and Make
• Ability to detect leaks, double-frees, dangling pointers, data races, and undefined behavior
• Strong understanding of pthreads, C11 threads, atomics, locks, and lock-free patterns
• Advanced use of ASan, UBSan, TSan, Valgrind, gdb or lldb, and unit-testing frameworks such as Unity, CMock, or Catch2
• Experience with profiling tools such as perf or VTune, cache-friendly design, and low-level tuning across multiple architectures
• Ability to identify CWE and OWASP issues, including buffer overflows, integer wrap, format-string vulnerabilities, and injection
• Knowledge of exploit mitigations such as stack canaries and ASLR
• Comfort with Dockerized toolchains, CI/CD pipelines, GitHub or GitLab pull requests, and code-review platforms
• Experience compiling and running code in sandbox or container environments
• Familiarity with Jira, Asana, or comparable ticketing and annotation tools
• Excellent written English at B2 CEFR or higher

Communication and Additional Experience

The strongest candidates can explain technical findings clearly, deliver concise and actionable feedback, and mentor peers on secure, maintainable C practices. Experience with AI evaluation or data-labeling workflows is helpful but not required as a stated qualification.

• Able to deliver precise written feedback
• Able to mentor peers on C development and review best practices
• Nice to have: experience with LLM evaluation or RLHF pipelines
• Nice to have: prior AI or machine-learning data-labeling experience

How to Apply Through OpenTrain

Create a free OpenTrain account, build your profile, and apply in minutes. OpenTrain connects qualified contributors with AI training projects where specialized technical knowledge directly improves the quality of AI systems.

• Select this Senior C Code Reviewer contract
• Highlight your C11/C18, testing, security, concurrency, and code-review experience
• Confirm your availability for 20+ hours per week
• Apply through OpenTrain