Software Engineer (Trajectory)

Mercor is hiring experienced Software Engineers to support high-impact research collaborations with leading AI labs. Freelancers will contribute to building training datasets that improve AI model reasoning and problem-solving on real-world coding tasks.

This is a unique opportunity to apply your software engineering expertise toward shaping the next generation of intelligent systems.

About the Project

You'll annotate frontier-model trajectories on SWE-bench–style tasks derived from real open-source repositories. Currently, closed-source models do not expose their internal reasoning traces, making it difficult to understand how LLMs approach problem-solving.

To address this gap, you'll reconstruct and annotate the reasoning portions of model trajectories—using your own problem-solving process and the full task context to infer and infill the underlying thought process at each step.

Key Responsibilities

• Review model-generated code trajectories on realistic software engineering tasks

• Reconstruct chain-of-thought reasoning that explains each step of the solution process

• Annotate decision points, debugging logic, and problem-solving strategies

• Use full task context (codebase, issue descriptions, test cases) to infer plausible reasoning

• Ensure annotations reflect realistic developer thought processes and technical accuracy

Ideal Qualifications

• 2+ years of experience in software engineering, with hands-on debugging and problem-solving in real codebases

• Degree in Software Engineering, Computer Science, or a related field (Bachelor's minimum; advanced degree preferred)

• Strong proficiency in Python, JavaScript, TypeScript, or other common languages found in open-source projects

• Familiarity with version control workflows (Git, PRs, issue tracking)

• Comfortable articulating technical reasoning in clear, structured writing

Project Timeline

• Start Date: Immediate

• Duration: 1–2 months

• Commitment: Part-time (15–25 hours/week, with flexibility up to 40 hours/week)

Application & Onboarding Process

1. Upload your resume

2. AI interview: A short, 15-minute conversational session to understand your background, experience, and interest in the role

3. Follow-up communication within a few days with next steps and onboarding details

Apply today and leverage your software engineering expertise to help build the future of AI-driven systems!

We consider all qualified applicants without regard to legally protected characteristics and provide reasonable accommodations upon request.

Contract and Payment Terms

• You will be engaged as an independent contractor.
• This is a fully remote role that can be completed on your own schedule.
• Projects can be extended, shortened, or concluded early depending on needs and performance.
• Your work at Mercor will not involve access to confidential or proprietary information from any employer, client, or institution.
• Payments are weekly on Stripe or Wise based on services rendered.
• Please note: We are unable to support H1-B or STEM OPT candidates at this time.

About Mercor

Mercor partners with leading AI labs and enterprises to train frontier models using human expertise. You will work on projects that focus on training and enhancing AI systems. You will be paid competitively, collaborate with leading researchers, and help shape the next generation of AI systems in your area of expertise.