Principal ML Architect – Security AI & Advanced Model Systems
Sunnyvale, CA - USA
Job Summary
About 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 Fortunelarge 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 youll 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.
You will drive the development of intelligent security-focused AI systems and agents capable of operating at scale across high-volume adversarial and sensitive environments while ensuring robustness explainability and compliance.
Key Responsibilities
AI Architecture for Security Systems
Design and lead architecture for AI-driven security platforms including:
Threat detection and behavioral analytics
Data loss prevention (DLP) and insider risk detection
AI usage monitoring and policy enforcement (GenAI security)
Build systems that process high-volume high-velocity security telemetry in real time
Model Development & Innovation
Lead development of state-of-the-art SLMs/LLMs tailored for security use cases:
Log analysis alert triage threat intelligence policy reasoning
Drive experimentation with modern architectures (Transformers MoE retrieval-augmented systems hybrid models)
Balance trade-offs between model accuracy latency interpretability and cost
Training Fine-Tuning & Distillation
Architect pipelines for:
Domain adaptation and instruction tuning on security-specific datasets
Model distillation and compression for efficient deployment in enterprise environments
Design and execute experiments for:
Alignment (RLHF/RLAIF) in security-sensitive contexts
Red-teaming and adversarial robustness of models
AI Agents for Security Workflows
Design and oversee AI agents that:
Automate security operations (SOC workflows triage investigation)
Integrate with enterprise tools (SIEM EDR SaaS platforms)
Define architectures for tool use reasoning memory and policy-aware decision making
Experimentation & Evaluation
Establish rigorous evaluation frameworks for:
Detection accuracy false positives/negatives
Model robustness under adversarial conditions
Safety hallucination and misuse risks
Lead deep experimentation cycles to continuously improve model performance and reliability
Productionization & Scale
Guide deployment of models into enterprise-scale real-time environments
Optimize inference systems for low latency high throughput and cost efficiency
Collaborate with platform teams on ML infrastructure data pipelines and observability
Security Governance & Responsible AI
Ensure models and systems meet enterprise security standards (SOC2 ISO GDPR etc.)
Establish best practices for:
Secure model development and deployment
Data privacy and protection in training pipelines
Responsible AI and model safety in adversarial environments
Required Qualifications
Experience
10 years in ML/AI systems with significant focus on deep learning and production ML
Proven experience in:
Building or scaling LLMs/SLMs or advanced ML systems
Applying ML/AI in security fraud risk or adversarial domains
Track record of delivering production-grade AI systems at scale
Technical Expertise
Deep understanding of:
Transformer architectures and modern LLM techniques
Retrieval-augmented generation (RAG) and hybrid AI systems
Model training dynamics scaling laws and optimization
Hands-on experience with:
Training fine-tuning and distilling models
Efficient inference (quantization pruning batching)
Distributed training frameworks (PyTorch DeepSpeed FSDP etc.)
Security Domain Knowledge
Strong understanding of one or more:
Security telemetry (logs network traffic endpoint data)
Threat detection and anomaly detection systems
Identity access and data protection systems
Familiarity with security tooling ecosystems (SIEM EDR CASB etc.)
Systems & Engineering
Experience designing high-throughput low-latency ML systems
Strong programming skills in Python with production experience
Understanding of data pipelines feature engineering and MLOps practices
Preferred Qualifications
Experience building AI systems for SaaS security or GenAI security platforms
Familiarity with multi-agent systems for security automation
Experience with synthetic data generation for security use cases
Contributions to AI/ML research open-source or security tooling
Background in AI safety adversarial ML or model interpretability
Success Metrics
Development of high-precision low-noise security AI models
Successful deployment of AI agents automating security workflows
Measurable improvements in detection accuracy and operational efficiency
Robustness of models against adversarial and real-world attack scenarios
Strong adherence to enterprise security privacy and compliance standards
Why This Role Matters
This role is central to building intelligent AI-native security systems that can operate at enterprise scale and under adversarial conditions. The Principal ML Architect will define the technical foundation for secure reliable and high-performance AI systems enabling the organization to lead in next-generation cybersecurity powered by AI.
Why Proofpoint
At Proofpoint we believe that an exceptional career experience includes a comprehensive compensation and benefits package. Here are just a few reasons youll love working with us:
Competitive compensation
Comprehensive benefits
Career success on your terms
Flexible work environment
Annual wellness and community outreach days
Always on recognition for your contributions
Global collaboration and networking opportunities
Our Culture:
Our culture is rooted in values that inspire belonging empower purpose and drive success-every day for everyone.
We encourage applications from individuals of all backgrounds experiences and perspectives. If you need accommodation during the application or interview process please reach out to .
How to Apply
Interested Submit your application along with any supporting information- we cant wait to hear from you!
Consistent with Proofpoint values and applicable law we provide the following information to promote pay transparency and equity. Our compensation reflects the cost of labor across several U.S. geographic markets and we pay differently based on those defined markets as set out below. Pay within these ranges varies and depends on job-related knowledge skills and experience. The actual offer will be based on the individual candidate. The range provided may represent a candidate range and may not reflect the full range for an individual tenured employee. This role may be eligible for variable compensation and/or equity. We offer a competitive benefits package including flexible time off a comprehensive well-being program with two paid Wellbeing Days and two paid Volunteer Days per year plus a three-week Work from Anywhere option.
Base Pay Ranges:
SF Bay Area New York City Metro Area:
Base Pay Range: 254000.00 - 349250.00 USDCalifornia (excludes SF Bay Area) Colorado Connecticut Illinois Washington DC Metro Maryland Massachusetts New Jersey Texas Washington Virginia and Alaska:
Base Pay Range: 208800.00 - 287100.00 USDAll other cities and states excluding those listed above:
Base Pay Range: 187000.00 - 257180.00 USDRequired Experience:
Staff IC