Principal ML Architect – Security AI & Advanced Model Systems
Proofpoint · Sunnyvale, CA
About this role
Proofpoint is hiring a principal-level Principal Engineer in the software engineering function based in Sunnyvale, CA. The posting calls out experience with Python, PyTorch, LLMs, RAG. Compensation is listed at $254,000–$349,250 per year.
- Role
- Principal Engineer
- Function
- software engineering
- Level
- principal
- Track
- Tech leadership
- Employment
- Full-time
- Location
- Sunnyvale, CA
- Posted
- May 12, 2026
More roles at Proofpoint
Job description
from Proofpoint careersAbout Us:
Proofpoint is a global leader in human- and agent-centric cybersecurity. We protect how people, data, and AI agents connect across email, cloud, and collaboration tools. Over 80 of the Fortune 100, 10,000 large enterprises, and millions of smaller organizations trust Proofpoint to stop threats, prevent data loss, and build resilience across their people and AI workflows. Our mission is simple: safeguard the digital world and empower people to work securely and confidently. Join us in our pursuit to defend data and protect people.
How We Work:
At Proofpoint you’ll be part of a global team that breaks barriers to redefine cybersecurity guided by our BRAVE core values:
Bold in how we dream and innovate
Responsive to feedback, challenges and opportunities
Accountable for results and best in class outcomes
Visionary in future focused problem-solving
Exceptional in execution and impact
Role Overview
We are seeking a Principal ML Architect to lead the design and development of next-generation AI systems for cybersecurity, leveraging state-of-the-art LLMs/SLMs and advanced machine learning techniques.
This role requires deep expertise in model architecture, training, fine-tuning, and distillation, combined with a strong understanding of security domains such as threat detection, anomaly detection, data protection, and AI safety.