AI Generalist Jobs Madrid 2026: Remote AI/ML Data Operations

Explore full-time and freelance AI Generalist jobs in Madrid for 2026 at Rex.zone. As an AI Generalist, you will power large language model evaluation, RLHF (Reinforcement Learning from Human Feedback), and training data quality pipelines. Whether you are seeking entry-level or senior remote roles, these opportunities involve prompt evaluation, content safety labeling, and NLP model performance improvement. Join leading AI labs and tech startups to shape the future of LLM training workflows. Discover contract and full-time remote opportunities tailored for Madrid-based professionals looking to advance in computer vision annotation and AI data operations.

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Senior AI Generalist — LLM Evaluation

Title: Senior AI Generalist Date: 25-02-2026 Company: Rexzone Country: ES Remote Type: Remote Employment Type: FULL_TIME Experience Level: Mid-Senior Industry: Technology Job Function: Engineering Skills: Large Language Model Evaluation, RLHF, Prompt Engineering, Training Data Quality, NLP Salary Currency: USD Salary Min: 63360 Salary Max: 126720 Pay Period: YEAR As a Senior AI Generalist based in Madrid (working remotely), you will lead large language model evaluation and RLHF initiatives. Your daily workflows will involve complex prompt evaluation, ensuring annotation guidelines compliance, and driving model performance improvement. You will collaborate with global AI labs through Rex.zone to refine training data quality across diverse NLP domains.

Remote AI/ML Data Annotation Specialist

Title: AI Data Annotation Specialist Date: 25-02-2026 Company: Rexzone Country: ES Remote Type: Remote Employment Type: FULL_TIME Experience Level: Mid-Senior Industry: Technology Job Function: Engineering Skills: Data Labeling, Computer Vision Annotation, Content Safety Labeling, Named Entity Recognition Salary Currency: USD Salary Min: 63360 Salary Max: 126720 Pay Period: YEAR This remote role focuses on comprehensive data labeling and QA evaluation for LLM training pipelines. You will execute named entity recognition, computer vision annotation, and content safety labeling to support foundational model development. Ideal for professionals seeking full-time AI Generalist jobs in Madrid 2026, this position requires strict adherence to annotation guidelines compliance and a deep understanding of AI/ML training workflows.

Frequently Asked Questions About AI Generalist Jobs in Madrid 2026

  • Q: What does an AI Generalist do at Rex.zone?

    An AI Generalist handles a wide range of AI/ML training workflows, including RLHF, data labeling, prompt evaluation, and QA evaluation to ensure training data quality for large language models.

  • Q: Are these AI Generalist roles in Madrid fully remote?

    Yes, all listed AI Generalist jobs in Madrid for 2026 are fully remote, offering flexible contract, freelance, and full-time opportunities for professionals across Spain.

  • Q: What skills are required for LLM training pipelines?

    Key skills include expertise in NLP, computer vision annotation, content safety labeling, named entity recognition, and a strong track record in model performance improvement.

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50+Countries Represented

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