STEM Careers in Brazil

STEM Careers in Brazil at Rex.zone focus on engineering work that supports AI/ML training workflows, including data labeling, RLHF evaluation, QA evaluation, and prompt evaluation to improve large language model performance. In this full-time remote role, you will apply annotation guidelines compliance, training data quality checks, and model performance improvement practices across NLP, computer vision, named entity recognition, and content safety labeling. You will collaborate with distributed teams, contribute to LLM training pipelines, and help AI labs, tech startups, and annotation vendors ship reliable datasets and evaluations. Explore and apply through Rex.zone to join a high-impact engineering function.

Job Image

Job Overview

Keyword: STEM Careers Brazil — Job Title: STEM Careers in Brazil Date: 25-02-2026 Company: Rexzone Country: US Remote Type: Remote Employment Type: FULL_TIME Experience Level: Mid-Senior Industry: Technology Job Function: Engineering Skills: STEM engineering, applied machine learning, LLM training pipelines, RLHF, data labeling, QA evaluation, prompt evaluation, NLP, named entity recognition, computer vision annotation, content safety labeling, annotation guidelines compliance Salary Currency: USD Salary Min: 63360 Salary Max: 126720 Pay Period: YEAR

About the Role

You will operate in a remote engineering capacity supporting STEM-aligned initiatives connected to AI/ML data operations and evaluation. Your work may include building and improving labeling workflows, reviewing annotation guidelines, running QA evaluation and adjudication, performing prompt evaluation for LLM behavior, and contributing to RLHF data quality. You will help ensure training data quality, reduce ambiguity in instructions, and document edge cases that affect large language model evaluation and model performance improvement.

What You Will Do

Required Qualifications

Preferred Qualifications

Work Model and Employment Details

How to Apply on Rex.zone

Frequently Asked Questions

  • Q: Is this role remote?

    Yes. Remote Type is Remote and the role is designed for full-time remote work.

  • Q: Why does a STEM engineering role include RLHF, data labeling, and LLM evaluation?

    Modern AI systems depend on high-quality training data and robust evaluation. This role supports LLM training pipelines through RLHF datasets, prompt evaluation, QA evaluation, and annotation guidelines compliance to drive model performance improvement.

  • Q: What kinds of tasks are included in data labeling and QA evaluation?

    Typical tasks include NLP labeling (classification, NER), computer vision annotation, content safety labeling, rubric-based grading, sampling for training data quality, and documenting edge cases for guideline updates.

  • Q: Is this position full-time or contract/freelance?

    This position is FULL_TIME. Rex.zone may list contract, freelance, or part-time roles separately, but this posting is full-time.

  • Q: What experience level is expected?

    The Experience Level is Mid-Senior, emphasizing independent execution, strong documentation, and consistent quality control in evaluation workflows.

  • Q: What domains might I work in (NLP, computer vision, content safety)?

    You may contribute across NLP, computer vision annotation, named entity recognition, prompt evaluation, RLHF, and content safety labeling depending on project needs and your strengths.

  • Q: What is the salary range and pay period?

    The salary range is 63360 to 126720 USD, paid on a YEAR basis.

230+Domains Covered
120K+PhD, Specialist, Experts Onboarded
50+Countries Represented

Industry-Leading Compensation

We believe exceptional intelligence deserves exceptional pay. Our platform consistently offers rates above the industry average, rewarding experts for their true value and real impact on frontier AI. Here, your expertise isn't just appreciated - it's properly compensated.

Work Remotely, Work Freely

No office. No commute. No constraints. Our fully remote workflow gives experts complete flexibility to work at their own pace, from any country, any time zone. You focus on meaningful tasks - we handle the rest.

Respect at the Core of Everything

AI trainers are the heart of our company. We treat every expert with trust, humanity, and genuine appreciation. From personalized support to transparent communication, we build long-term relationships rooted in respect and care.

Ready to Shape the Future of Engineering?

Apply Now.