Principal LLM Engineer

Principal LLM Engineer

Join Rapid7 : Secure the Future with AI

Are you ready to lead the charge in integrating cutting-edge Large Language Models (LLMs) into world-class Cyber Security products?

Rapid7 is looking for a Principal LLM Engineer with a rare combination of deep Data Science expertise, mastery of production MLOps, and 13+ years of experience. You won't just build models; you'll architect the AI systems that protect our customers from the world's most sophisticated threats. This is a role for a proven leader who turns breakthrough research into scalable, high-impact security solutions.

What You'll Be Doing : Technical Leadership

As a Principal Engineer, you will define and execute the technical strategy across three critical domains :

1. LLM & AI System Architecture

You'll design and build the next generation of AI-powered security features.

LLM Orchestration : Architect complex security applications using frameworks like LangChain and LangGraph to connect LLMs with our data and tools.

RAG Pipelines : Build and optimise high-performance Retrieval-Augmented Generation (RAG) systems using Vector DBs to give our AI the context it needs from vast security datasets.

Model Optimisation : Implement efficient adaptation techniques ( LoRA / PEFT ) and run rigorous evaluation using tools like Promptfoo / HELM to ensure model accuracy and safety.

Governance & Safety : Design and enforce security Guardrails and governance policies for all LLM deployments.

2. Security-Focused MLOps & Production

You'll ensure our AI is always live, stable, and fighting threats.

Real-Time Monitoring : Establish comprehensive monitoring with Prometheus / Grafana / CloudWatch and lead our response to production incidents ( PagerDuty, On-call ).

Model Life Cycle : Master the MLOps pipeline, from model versioning ( MLflow / SageMaker ) to automating Drift Detection & Retraining .

Infrastructure : Use Terraform and Docker / Kubernetes to deploy scalable microservices and APIs.

Cloud Security Integration : Leverage AWS Bedrock / SageMaker / Lambda and ensure all deployments adhere to the highest standards of Cloud Security (IAM, VPC, Secrets) .

CI / CD : Drive continuous deployment for our AI systems using tools like GitHub Actions / Jenkins .

3. Data Science & Security Foundation

Your background will enable you to solve complex security problems with data.

Deep Learning : Apply expertise in NLP, CNN, RNN, etc. to analyse security data (logs, network traffic, etc.).

Security Models : Drive the development of Malware Detection models , User behavioural models , and Malware behaviour-based Models .

Data Engineering : Lead initiatives in Data Acquisition, Feature Engineering , and transformation across services like S3, DynamoDB, and Redshift .

Explainable AI (XAI) : Use SHAP / LIME to ensure transparency and explainability in security decisions made by AI.

What You'll Bring

13+ years of professional experience in Data Science, with a significant focus on LLMs / NLP and production MLOps.

Advanced degree (Master's or PhD) in Computer Science, Data Science, or a related field, or equivalent practical experience.

A proven track record of taking complex ML / LLM projects from concept to highly available production systems.

Familiarity with Cost Optimisation (FinOps) for cloud resources.

If you thrive on solving the hardest problems in AI and applying that power to make the world a safer place, we want to hear from you!