Senior Machine Learning Engineer

Senior Machine Learning Engineer (AI Data Trainer) About The Role What if your deep expertise in machine learning could directly shape how the next generation of AI systems reason, plan, and make decisions? We're looking for Senior Machine Learning Engineers to author high-fidelity reasoning traces that train large language models to think more reliably in real-world scenarios. This is a fully remote, flexible contract role built for experienced ML practitioners who understand how models learn — and want to influence that process at its core. • Organization: Alignerr • Type: Hourly Contract • Location: Remote • Commitment: 10–40 hours/week What You'll Do • Author complex, high-fidelity reasoning traces that capture step-by-step planning, tool use, and decision-making for sophisticated technical tasks • Design and document structured traces that show how an LLM should navigate real-world problem-solving scenarios • Review and mentor the quality of reasoning traces to ensure optimal clarity, logical flow, and technical accuracy • Develop data strategies that help LLMs handle intricate, multi-step challenges with greater reliability • Apply senior-level architectural insight to ensure traces reflect sound model reasoning principles • Work independently and asynchronously — fully on your own schedule Who You Are • Experienced machine learning practitioner with a strong focus on model reasoning, planning, and decision-making • Proven ability to decompose complex problems into clear, logical, well-documented steps • Deep familiarity with LLM evaluation and training methodologies • Systematic and detail-oriented — you think carefully about how reasoning should be structured and communicated • Strong written communicator who can translate complex technical logic into readable, structured documentation • Self-motivated and reliable when working independently Nice to Have • Prior experience with data annotation, data quality assurance, or evaluation systems • Top-tier Kaggle competition results (Grandmaster or Master level) — a strong signal of deep understanding of model performance and feature engineering • Background in AI safety, interpretability, or alignment-adjacent research • Experience designing training data pipelines or annotation frameworks Why Join Us • Work directly with teams building cutting-edge AI at leading research labs • Fully remote and flexible — work when and where it suits you • Freelance autonomy with the structure of meaningful, high-impact technical work • Gain rare, hands-on insight into how frontier LLMs are trained to reason • Contribute to work that meaningfully improves how AI systems make decisions at scale • Potential for ongoing work and contract extension as new projects launch