Senior ML Engineer: LLMs, RAG & Production-Grade Systems

Flagship Pioneering, Inc.; Cambridge (MA); On-site; USD 150,000 - 190,000; Full time

Benefits offered by this job

Healthcare coverage

Annual incentive program

Retirement benefits

Broad range of other benefits

Job summary

Flagship Pioneering in Cambridge, MA seeks a Senior Machine Learning Engineer to design, build, and deploy ML systems powering our platform. You’ll focus on LLMs, RAG, agentic orchestration, and production-grade deployment, working across the full ML lifecycle with scientists and engineers in a fast-moving, mission-driven environment.

You will own data pipelines, experiment with models, fine-tune for production, and contribute to ML best practices and architecture decisions.

Qualifications

• Master's degree or equivalent practical experience in CS/ML/AI.
• 5+ years of professional ML experience.
• Strong ML, DL, and NLP foundations.
• Proven production deployment of LLM-powered apps.
• Experience with RAG, orchestration, and multi-agent systems preferred.
• Proficiency in Python and ML tooling; end-to-end ownership.

Responsibilities

• Design, build, and deploy ML systems powering the product.
• Architect scalable RAG-LLM based solutions with multi-modal data.
• Develop agentic orchestration frameworks for end-to-end reasoning.
• Own ML pipeline from data collection to deployment and monitoring.
• Fine-tune and evaluate LLMs for production use with focus on reliability and cost.
• Establish lightweight MLOps, CI/CD, reproducibility, and experiment tracking.
• Balance off-the-shelf APIs with custom fine-tuned solutions.
• Influence ML best practices across the team; collaborate cross-functionally.
• Translate interdisciplinary insights into computational frameworks.
• Clearly communicate tradeoffs to technical and non-technical stakeholders.

Skills

LLMs

RAG

Agentic orchestration

Python

PyTorch

vLLM

LangGraph

Data pipelines

MLOps

CI/CD

Production monitoring

NLP

Communication

Education

Master's degree in CS/ML/AI

Tools

PyTorch

vLLM

LangGraph

Job description

Flagship Pioneering in Cambridge, MA seeks a Senior Machine Learning Engineer to design, build, and deploy ML systems powering our platform. You’ll focus on LLMs, RAG, agentic orchestration, and production-grade deployment, working across the full ML lifecycle with scientists and engineers in a fast-moving, mission-driven environment.

You will own data pipelines, experiment with models, fine-tune for production, and contribute to ML best practices and architecture decisions.