Posted Sep 14, 2026

Senior Data Labeling Specialist (Boston)

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Senior Data Labeling Jobs in Boston (Remote, Full-Time) Rex.zone is hiring senior data labeling professionals to lead training data quality for AI/ML systems. This role combines data labeling, RLHF evaluation, prompt evaluation, and QA to improve large language model performance across end-to-end LLM training pipelines. What You Will Do • Lead complex data labeling and QA evaluation for LLM training pipelines • Execute RLHF-style preference ranking and rubric-based prompt evaluation • Create, refine, and enforce annotation guidelines; drive annotator calibration • Perform named entity recognition and taxonomy-based labeling for NLP datasets • Support computer vision annotation workflows (bounding boxes, polygons, keypoints) as needed • Run quality audits, disagreement analysis, and error taxonomy reporting • Flag ambiguous edge cases and collaborate with engineering and ops on policy updates • Maintain documentation for annotation guidelines compliance and audit readiness • Track quality metrics (accuracy, inter-annotator agreement) and recommend process changes Required Qualifications • Experience leading or mentoring labelers in production annotation programs • Strong understanding of training data quality, quality assurance, and evaluation rubrics • Hands-on experience with RLHF-style ranking, LLM evaluation, or prompt evaluation • Familiarity with named entity recognition and structured labeling schemas • Ability to document decisions clearly and apply policy consistently • Excellent attention to detail and ability to deliver high accuracy at scale Work Model Remote role within the US, aligned to Boston-area schedules and availability. Includes scheduled calibration and QA review sessions to maintain consistent quality. Compensation Hourly base pay: $30–$50 (USD), based on scope, domain complexity, and demonstrated quality leadership. FAQ Highlights • Remote? Yes—work is performed remotely within the US, with Boston alignment. • What is “senior data labeling”? Owning training data quality: QA evaluation, calibration, guideline compliance, and edge case resolution. • Task types? RLHF preference ranking, prompt evaluation, NER, content safety labeling, and (as needed) computer vision annotation.