Most In Demand STEM Jobs Brazil

This page highlights the most in demand STEM jobs in Brazil and how they map to real-world AI/ML delivery work on Rex.zone, including LLM training pipelines, RLHF evaluation, data labeling, QA evaluation, and production engineering. These remote, full-time roles reflect the skills employers seek most—software engineering, data engineering, machine learning, cloud, cybersecurity, and computer vision—while emphasizing training data quality, annotation guidelines compliance, and model performance improvement. Explore roles, review LinkedIn-ready metadata, and apply through Rex.zone to join teams building and evaluating modern AI systems.

Job Image

Machine Learning Engineer

Title: Machine Learning Engineer 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: Machine Learning, LLM Training Pipelines, Model Evaluation, RLHF, Prompt Evaluation, Feature Engineering, Python, MLOps Salary Currency: USD Salary Min: 63360 Salary Max: 126720 Pay Period: YEAR Build, train, and evaluate ML systems used in product features and AI/ML training workflows. You will improve model performance through data-centric iteration, offline/online evaluation, and training data quality practices. Work closely with data labeling teams to define annotation guidelines compliance, leverage RLHF signals where appropriate, and run prompt evaluation and QA evaluation loops for large language model evaluation. Typical projects include ranking models, classifiers, retrieval augmentation metrics, and model monitoring in production.

Data Engineer

Title: Data Engineer 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: Data Pipelines, ETL, SQL, Python, Spark, Data Warehousing, Airflow, Data Quality Salary Currency: USD Salary Min: 63360 Salary Max: 126720 Pay Period: YEAR Own scalable data pipelines that power analytics, ML features, and LLM training pipelines. You will build reliable ETL/ELT processes, enforce training data quality, and create datasets used for data labeling, named entity recognition, and large-scale evaluation. This role supports AI/ML teams by ensuring clean, well-documented data assets, lineage, and auditability for QA evaluation and model performance improvement.

Software Engineer

Title: Software Engineer 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: Backend Development, APIs, Distributed Systems, Python, Java, Microservices, Testing, Cloud Salary Currency: USD Salary Min: 63360 Salary Max: 126720 Pay Period: YEAR Build production systems that serve AI products and the tooling behind LLM training pipelines. You will implement services for data ingestion, annotation workflow management, QA evaluation dashboards, and model inference at scale. The work often intersects with data labeling platforms, content safety labeling queues, and large language model evaluation pipelines that require strong reliability engineering and high test coverage.

Cybersecurity Engineer

Title: Cybersecurity Engineer 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: Security Engineering, Threat Modeling, Incident Response, IAM, Cloud Security, SIEM, Vulnerability Management, Secure SDLC Salary Currency: USD Salary Min: 63360 Salary Max: 126720 Pay Period: YEAR Protect platforms and AI/ML pipelines by embedding security into infrastructure, applications, and data operations. You will secure datasets used in data labeling and large language model evaluation, implement access controls for RLHF feedback and prompt evaluation logs, and strengthen secure SDLC practices. This role supports compliance, risk reduction, and operational resilience across remote teams.

Cloud Engineer

Title: Cloud Engineer 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: Cloud Infrastructure, AWS, Terraform, Kubernetes, CI/CD, Observability, Networking, Cost Optimization Salary Currency: USD Salary Min: 63360 Salary Max: 126720 Pay Period: YEAR Build and operate cloud infrastructure that supports ML training, LLM training pipelines, and high-throughput data labeling operations. You will provide scalable compute, secure networking, and observability for evaluation services including RLHF evaluation, prompt evaluation, and QA evaluation workloads. This role focuses on reliability, automation, and cost optimization for remote-first engineering teams.

Computer Vision Engineer

Title: Computer Vision Engineer 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: Computer Vision, CV Annotation, Image Labeling, Object Detection, Segmentation, PyTorch, Model Evaluation, Data Labeling Salary Currency: USD Salary Min: 63360 Salary Max: 126720 Pay Period: YEAR Develop and evaluate computer vision models and the data pipelines that make them accurate. You will define CV annotation strategies (bounding boxes, polygons, segmentation masks), enforce annotation guidelines compliance, and improve training data quality through review and QA evaluation. Work includes model performance improvement via dataset curation, active learning loops, and robust offline evaluation for detection and segmentation systems.

NLP Engineer

Title: NLP Engineer 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: NLP, LLM Evaluation, Named Entity Recognition, Text Classification, RLHF, Prompt Evaluation, Python, Data Labeling Salary Currency: USD Salary Min: 63360 Salary Max: 126720 Pay Period: YEAR Build NLP systems and evaluation methods for large language models and classic language tasks. You will design annotation schemas for named entity recognition, content safety labeling, and text classification, then use QA evaluation and prompt evaluation to measure quality. This role improves LLM training pipelines by iterating on datasets, leveraging RLHF where appropriate, and establishing reproducible evaluation that correlates with real user outcomes.

Frequently Asked Questions

  • Q: What does “most in demand STEM jobs Brazil” mean on Rex.zone?

    It refers to STEM roles that are consistently in high demand in Brazil’s market (software, data, ML, cloud, cybersecurity, CV, NLP) and are commonly offered as remote, full-time positions on Rex.zone for teams building modern AI systems.

  • Q: Are these roles remote and full-time?

    Yes. Each role on this page is explicitly listed as Remote and FULL_TIME, matching common search modifiers like remote and full-time.

  • Q: How do these jobs connect to AI/ML workflows like RLHF and data labeling?

    Many in-demand STEM roles now intersect with LLM training pipelines, including RLHF evaluation, prompt evaluation, QA evaluation, data labeling, named entity recognition, computer vision annotation, and content safety labeling to improve training data quality and model performance.

  • Q: Do I need prior experience with LLM evaluation to apply?

    Not always, but mid-senior candidates are expected to learn and apply evaluation practices such as rubric scoring, offline metrics, and QA evaluation loops, especially when working with large language model evaluation and training data quality.

  • Q: What employer types hire for these roles?

    AI labs, tech startups, enterprises, BPOs, annotation vendors, and platform teams commonly hire for these roles, especially for building data pipelines, secure infrastructure, and evaluation systems.

  • Q: Does the page cover contract or freelance roles too?

    This page is configured for FULL_TIME roles, but it includes common modifiers (contract, freelance, entry-level, senior) to match how candidates search; Rex.zone may list additional employment types on other pages.

  • Q: How should I choose which role fits me best?

    Pick based on your strongest skill cluster: ML Engineer (modeling + MLOps), Data Engineer (pipelines + quality), Software Engineer (services + systems), Cloud Engineer (infra + automation), Cybersecurity Engineer (secure SDLC + incident response), CV Engineer (vision + CV annotation), NLP Engineer (language + LLM evaluation).

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.