Machine Learning Engineer (AI Data Trainer) About The Role What if your technical expertise could directly influence how the world's most advanced AI systems learn to reason, plan, and solve problems? We're looking for Machine Learning Engineers to help train cutting-edge AI models by demonstrating expert-level problem-solving — step by step, tool by tool, decision by decision. This isn't a typical ML engineering role.

You'll be working at the frontier of AI development, producing the high-quality reasoning data that teaches large language models how to think like an expert. Your work will have a direct, lasting impact on how AI handles real-world technical challenges. This is a fully remote, flexible contract role built for experienced technical professionals who want to contribute to something genuinely significant.

Organization: Alignerr

Type: Hourly Contract

Location: Remote

Commitment: 10–40 hours/week What You'll Do Construct precise, well-structured reasoning logs that walk through complex technical problems — capturing your strategy, tool use, and decision-making at each step

Demonstrate how an expert approaches sophisticated ML and engineering challenges, producing training data that shows AI models how to reason consistently and reliably

Generate annotated workflows that illustrate proficient tool interaction, from problem framing through to solution execution

Review and critically evaluate AI-generated reasoning sequences, identifying gaps, errors, and opportunities for improvement





Produce high-quality training datasets that directly improve LLM performance on real-world technical tasks Who You Are Professional background in Machine Learning, Software Engineering, or a closely related technical discipline

Able to clearly articulate complex reasoning processes — you can explain not just what you did, but why, step by step

Strong critical thinker with the ability to evaluate and refine AI-generated problem-solving approaches

Comfortable working independently and asynchronously with minimal supervision

Detail-oriented and methodical — you care about precision and consistency Nice to Have Master's Degree or PhD in Machine Learning, Computer Science, or a related technical field

Prior experience with data annotation, data quality assurance, or AI evaluation systems

Familiarity with LLMs, prompt engineering, or AI reasoning frameworks

Experience documenting technical workflows or writing technical specifications Why Join Us Work directly with leading AI research labs on projects shaping the next generation of AI

Fully remote and adaptable — structure your hours around your life, not the other way around

Freelance autonomy: choose your own pace, work asynchronously, and collaborate globally

Gain deep, hands-on exposure to how frontier LLMs are built and trained

Contribute to work that genuinely matters — your expertise helps make AI smarter and more reliable for everyone

Potential for ongoing work and contract extension as new projects launch

📌 Machine Learning Engineer (España)
🏢 Alignerr
📍 España