STEM Jobs in Brazil at Rex.zone connect Mid-Senior engineers and technical professionals with Remote, FULL_TIME roles supporting modern technology delivery and AI/ML training workflows. You will contribute to data labeling, RLHF evaluation, prompt evaluation, QA evaluation, and model performance improvement through reliable engineering practices. These roles support large language model evaluation, training data quality, annotation guidelines compliance, and production-ready systems for AI labs, tech startups, BPOs, and annotation vendors. Explore Rex.zone to find remote STEM opportunities aligned to Brazil-focused hiring needs while working with global teams and measurable outcomes.
Title: STEM Engineer (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: Python, Data Engineering, Machine Learning, NLP, Computer Vision, RLHF, Data Labeling, QA Evaluation, Prompt Evaluation, LLM Evaluation Salary Currency: USD Salary Min: 63360 Salary Max: 126720 Pay Period: YEAR
You will deliver engineering work that supports STEM initiatives tied to Brazil-focused hiring needs while operating as a Remote, full-time contributor. Projects may include building and maintaining data pipelines for training data quality, implementing annotation tooling, running QA evaluation, and supporting RLHF evaluation workflows used in large language model evaluation. You will collaborate with cross-functional stakeholders to translate requirements into reliable services, enforce annotation guidelines compliance, and help drive model performance improvement across NLP and computer vision tasks.
Own engineering deliverables across data systems, ML support tooling, and evaluation workflows; design and operate scalable pipelines for data labeling and content safety labeling; implement automated QA checks, sampling plans, and audit trails for evaluation datasets; support prompt evaluation, rubric design, and measurement for LLM evaluation; partner with AI labs, tech startups, BPOs, and annotation vendors to align outputs to project KPIs; document systems, test plans, and operational runbooks to ensure repeatability and compliance.
Mid-Senior experience delivering production engineering work; strong Python skills and ability to build maintainable services and data pipelines; familiarity with ML concepts including NLP, computer vision, and large language model evaluation; practical understanding of data labeling, annotation guidelines compliance, and training data quality; experience with QA evaluation methods, error analysis, and metrics-driven iteration; strong written communication and ability to work effectively in remote teams.
Experience supporting RLHF evaluation or preference data workflows; exposure to prompt evaluation and rubric-based scoring for LLM training pipelines; experience with dataset versioning, governance, and auditability; familiarity with content safety labeling and policy-driven annotation; experience collaborating with annotation vendors and distributed operations teams.
Search Rex.zone for "STEM Jobs in Brazil" to view current Remote, FULL_TIME openings. Apply with a resume highlighting engineering impact, ML-adjacent systems, data labeling or evaluation experience, and examples of model performance improvement through better training data quality.
It refers to Brazil-focused STEM hiring needs presented through Rex.zone, typically engineering roles that can be performed remotely while supporting technology delivery and AI/ML training workflows such as data labeling, QA evaluation, and large language model evaluation.
Yes. The roles on this page are explicitly marked Remote and FULL_TIME, aligned with the job metadata.
Common work includes building data pipelines, supporting LLM training pipelines, improving training data quality, implementing evaluation tooling, coordinating annotation guidelines compliance, and contributing to RLHF evaluation and prompt evaluation processes.
Typical domains include NLP, computer vision annotation support, content safety labeling, and large language model evaluation, depending on the team and project scope.
Projects commonly support AI labs, tech startups, BPOs, and annotation vendors that need engineering support for data operations and evaluation systems.
Highlight Python, data engineering, ML fundamentals, QA evaluation, data labeling systems, prompt evaluation, RLHF familiarity, and examples of improving model performance through better datasets and robust evaluation.
This page is configured for FULL_TIME roles, but Rex.zone may also list contract or freelance openings elsewhere. Search modifiers like "contract" or "freelance" on Rex.zone to find those options.
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