Senior C Software Engineer - Remote Codebase Explorer

Obsidian; San Francisco (CA); Remote; USD 60,000 - 120,000; Full time

Job summary

Mercor is seeking experienced C engineers to build a dataset that teaches AI agents to reason about real codebases. You will work on challenging C projects, exploring large codebases and their histories across production repositories.

This fully remote role pays per approved task and operates within Mercor Studio, with experts across multiple time zones. You will contribute to high-stakes tasks requiring careful analysis and precise documentation.

Qualifications

• 3+ years of professional software engineering experience, with substantial production C.
• Ability to navigate a large unfamiliar C codebase and explain runtime behavior.
• Comfort with preprocessor-heavy builds, platform conditionals, manual memory management, and build graphs.
• Experience with databases, cryptography, networking, or systems programming is relevant.
• Ability to use debuggers, sanitizers, tracing, and profilers to determine code behavior.
• Precise written English: your questions and rubrics are the product.

Responsibilities

• Select tasks from a pre-validated pool of C repositories, each pinned to a specific git commit.
• Explore the repository to understand the subsystem and relevant history.
• Rewrite tasks to defeat frontier agents while staying well-defined.
• Adjust rubrics and foils to reward correct reasoning.
• Run the full validation loop in Studio and iterate until it passes.
• Document work in task README and address reviewer feedback.

Skills

C programming

Codebase navigation

Debugging and profiling

Written English precision

Job description

Mercor is seeking experienced C engineers to build a dataset that teaches AI agents to reason about real codebases. You will work on challenging C projects, exploring large codebases and their histories across production repositories.

This fully remote role pays per approved task and operates within Mercor Studio, with experts across multiple time zones. You will contribute to high-stakes tasks requiring careful analysis and precise documentation.