Frontier AI & RL Research Engineer — Global Impact

Braintrust; United States; Hybrid; USD 30,000 - 42,000; Full time

Job summary

Braintrust is seeking a Staff Research Engineer to advance frontier AI and reinforcement learning initiatives. You will work across synthetic and agentic data, model understanding, and evaluation, building research-grade prototypes and scalable AI systems.

Expected project length is three months, with an immediate start. Availability of 40 hours per week, 8 hours per day and four hours of daily Pacific Time overlap is required. LinkedIn profile in resume is requested.

Qualifications

• 7+ years of research engineering experience in machine learning or frontier AI.
• PhD or Master’s in AI/ML/CS or exceptional equivalent research experience.
• Strong foundations in ML and designing experiments.
• Experience in synthetic or agentic data generation, RL, or AI evaluation.
• Strong Python programming and modern ML tooling.
• Scientific judgment with reproducible methods and data quality.
• Excellent written and verbal communication; cross-functional collaboration.
• Experience mentoring engineers or researchers and providing technical leadership.

Responsibilities

• Investigate frontier-model capabilities, limitations and training methods; formulate research questions.
• Build datasets, experiments, prototypes, tooling and evaluation frameworks; train and evaluate models.
• Analyze results with rigor; ensure reproducibility and evidence-based interpretation.
• Collaborate across Research, Engineering, Product and Operations to translate findings into systems.
• Communicate findings via technical reports, publications and peer review; provide mentorship.

Skills

Python programming

Cross-functional collaboration

Experiment design

ML frameworks & tooling

Education

PhD or Master’s in AI/ML/CS

Tools

TensorFlow

PyTorch

Job description

Braintrust is seeking a Staff Research Engineer to advance frontier AI and reinforcement learning initiatives. You will work across synthetic and agentic data, model understanding, and evaluation, building research-grade prototypes and scalable AI systems.

Expected project length is three months, with an immediate start. Availability of 40 hours per week, 8 hours per day and four hours of daily Pacific Time overlap is required. LinkedIn profile in resume is requested.