Senior Data Annotator Jobs in Portland (Remote)

Senior data annotator jobs in Portland focus on creating and evaluating training data that powers AI/ML systems on Rex.zone. In this full-time remote role, you will label and verify text, image, audio, and conversation data for large language model evaluation, RLHF, prompt evaluation, and content safety labeling. You will apply annotation guidelines compliance, run QA evaluation checks, and document edge cases that affect model performance improvement. This work supports LLM training pipelines, NLP tasks like named entity recognition, and computer vision annotation, helping AI labs, tech startups, annotation vendors, and BPO teams improve training data quality while scaling reliable human feedback.

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Job Opening: Senior Data Annotator (Portland, Remote)

Title: Senior Data Annotator (Portland, Remote) | Date: 25-02-2026 | Company: Rex.zone | Country: US | Remote Type: Remote | Employment Type: FULL_TIME | Experience Level: Mid-Senior | Industry: Technology | Job Function: Engineering | Skills: Data annotation, Data labeling, RLHF, LLM evaluation, Prompt evaluation, QA evaluation, Annotation guidelines, Training data quality, Named entity recognition, Computer vision annotation, Content safety labeling, Taxonomy and ontology | Salary Currency: USD | Salary Min: 63360 | Salary Max: 126720 | Pay Period: YEAR

About the Role

You will deliver high-quality labeled datasets and human feedback signals for AI/ML training workflows. Your annotations will support supervised fine-tuning, RLHF preference data, evaluation benchmarks, and content policy enforcement. You will work from Portland in a remote capacity, collaborating asynchronously with project leads to calibrate decisions, reduce ambiguity, and improve dataset consistency across batches.

What You Will Do

Perform expert-level data labeling across modalities: NLP text classification, named entity recognition, summarization quality checks, and dialogue evaluation for LLMs Create RLHF preference judgments and rationales for pairwise ranking, instruction following, and helpfulness/harmlessness criteria Run QA evaluation workflows: spot checks, inter-annotator agreement reviews, adjudication support, and error taxonomies Annotate computer vision data when needed (bounding boxes, polygons, keypoints) and verify label accuracy against guidelines Conduct prompt evaluation and model output grading for factuality, safety, tone, policy compliance, and refusal quality Document edge cases, propose guideline updates, and produce clear feedback that improves training data quality and model performance improvement

Required Qualifications

Mid-Senior experience performing data annotation, data labeling, or QA evaluation in production environments Demonstrated ability to interpret and apply complex annotation guidelines with high consistency Hands-on experience with LLM evaluation, prompt evaluation, RLHF, or human feedback workflows Strong written reasoning skills for explaining labels, preferences, and safety decisions Comfort working remotely with versioned instructions, batch tracking, and deadline-driven throughput expectations

Preferred Qualifications

Experience with named entity recognition, taxonomy/ontology design, and annotation schema refinement Exposure to content safety labeling, trust & safety policy enforcement, or red-teaming style evaluation Experience with computer vision annotation tools and visual QA processes Familiarity with benchmark creation, evaluation rubrics, and calibration sessions to improve inter-annotator agreement

Tools and Workflow

Annotation platforms for task queues, labeling interfaces, and audit logs QA evaluation methods including sampling plans, disagreement analysis, and adjudication notes Guideline versioning and change management to keep annotation guidelines compliance consistent Secure handling of sensitive datasets and content safety labeling procedures where applicable

Employment Details

Remote Type: Remote (Portland-based candidates welcome; work is performed remotely) Employment Type: FULL_TIME Salary Range: 63360 to 126720 USD per year (Pay Period: YEAR) Industry: Technology | Job Function: Engineering Apply/Explore: Find and apply to relevant senior data annotator jobs on Rex.zone

Frequently Asked Questions

  • Q: What does a senior data annotator do in AI/ML training?

    A senior data annotator produces high-quality labeled data and evaluation signals used to train and assess models. Typical work includes data labeling, RLHF preference judgments, prompt evaluation, QA evaluation audits, and documenting edge cases to improve training data quality and model performance improvement.

  • Q: Are these senior data annotator jobs in Portland remote?

    Yes. The role is explicitly marked Remote and is performed remotely, with Portland used as a location modifier for search intent and candidate targeting.

  • Q: What kinds of projects are included (NLP, computer vision, content safety, LLMs)?

    Projects commonly span NLP tasks like named entity recognition and text classification, large language model evaluation and RLHF, computer vision annotation, and content safety labeling for policy compliance and risk reduction in production AI systems.

  • Q: What is RLHF and why does it matter for this role?

    RLHF (Reinforcement Learning from Human Feedback) uses human preference data to guide model behavior. Senior annotators help create consistent preference judgments, rationales, and rubrics that improve instruction following, helpfulness, and safety in LLM training pipelines.

  • Q: What is QA evaluation in data annotation workflows?

    QA evaluation is the process of checking annotation correctness and consistency using audits, sampling, disagreement review, adjudication, and guideline compliance checks. It reduces label noise and improves dataset reliability.

  • Q: Which employers typically hire senior data annotators?

    Common employer types include AI labs, tech startups, annotation vendors, and BPO organizations supporting enterprise AI programs. Roles may involve production labeling, evaluation operations, and content safety labeling at scale.

  • Q: Is this a full-time role and what is the salary range?

    Yes, it is FULL_TIME. The salary range is 63360 to 126720 USD per YEAR, as listed in the job metadata.

  • Q: How do I apply or find similar roles on Rex.zone?

    Use Rex.zone to explore and apply to senior data annotator jobs, including remote, full-time, contract, freelance, entry-level, and senior roles across NLP, computer vision, content safety, and LLM evaluation tracks.

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