STEM Research Engineer (Brazil)

STEM Research Jobs in Brazil at Rex.zone

Join a full-time, remote STEM research-focused engineering role improving AI/ML training pipelines through applied research, evaluation, and data operations. You will translate research questions into measurable studies, create datasets and evaluation protocols, and strengthen large language model evaluation tied to training data quality and model performance improvement.

Key Responsibilities

* Design and run experiments that measure model behavior and data quality impacts

* Build and analyze datasets for named entity recognition, content safety labeling, and model evaluation

* Create annotation guidelines and ensure annotation guidelines compliance across contributors

* Execute RLHF evaluation and prompt evaluation workflows; document rubrics and edge cases

* Perform QA evaluation on labeled data and evaluations to reduce noise and bias

* Collaborate with engineering teams to integrate findings into training iterations

* Maintain reproducible research practices: versioning, documentation, and audit-ready artifacts

* Track metrics tied to evaluator agreement, training data quality, and performance improvement

Required Qualifications

* Mid-Senior experience in STEM research, engineering R&D, or applied research

* Strong experimental design, statistical reasoning, and data analysis skills

* Proficiency with Python and common data/science tooling

* Ability to write research documentation that is clear, testable, and reproducible

* Familiarity with machine learning fundamentals and evaluation methods

* Comfort working remotely with cross-functional stakeholders

Compensation

* $30–$50 per hour (USD), based on skills and experience