Staff AI Engineer

About Us:
We are the leader in human-centric cybersecurity. Half a million customers, including 87 of the Fortune 100, rely on Proofpoint to protect their organizations. We’re driven by a mission to stay ahead of bad actors and safeguard the digital world. 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.

Corporate Overview

Proofpoint is a leading cybersecurity company protecting organizations’ greatest assets and biggest risks: vulnerabilities in people. With an integrated suite of cloud-based solutions, Proofpoint helps companies around the world stop targeted threats, safeguard their data, and make their users more resilient against cyber-attacks. Leading organizations of all sizes, including more than half of the Fortune 1000, rely on Proofpoint for people-centric security and compliance solutions mitigating their most critical risks across email, the cloud, social media, and the web. 

We are singularly devoted to helping our customers protect their greatest assets and biggest security risk: their people. That’s why we’re a leader in next-generation cybersecurity. 

Why this role matters 

You’ll help build our core domain-specific LLM system, leading efforts across high-quality data creation, large-scale training, and efficient inference. Your work will help pioneer new AI defences for Proofpoint. 

What you’ll do 

• End-to-end LLM pipelines 
  Design, run and optimize distributed pre-training & fine-tuning workflows. 

• Curate gold-standard data 
  Collect, label and validate textual datasets for malicious-intent modelling. 

• Production integration 
  Ship models into our privacy-attested platform with reliable, scalable inference. 

• Rapid experimentation 
  Prototype & document techniques (distillation, quantization, RL-based tuning), track key ML metrics, and share clear learnings. 

• Cross-team partnership 
  Collaborate with infra, data-platform, product and research peers to translate ideas into production use cases. 

• Mentor & support others 
  Guide junior engineers and share knowledge across the team through reviews, pairing, and technical leadership. 

What you bring 

(We know no one checks every box, this is our ideal list.) 

• Deep LLM hands-on: You’ve tackled pre-training or post-training (fine-tuning/RL) at scale, on either open-source or closed models. 

• Strong ML fundamentals: Solid Python + PyTorch/TensorFlow experience, with real-world training and inference examples. 

• Data-pipeline fluency: Comfortable using Airflow/Flyte (or equivalent) and cloud storage (e.g. S3, BigQuery). 

• Production engineering: Familiar with model CI/CD, versioning, monitoring and performance tuning in cloud environments. 

• Curiosity: You stay ahead of LLM trends, propose testable hypotheses, and see experiments through to actionable conclusions. 

Nice-to-haves: multi-GPU optimization (distillation/quant), cybersecurity-domain AI (phishing/anomaly detection), secure-by-design coding & data-privacy practices. 

How we’ll track progress 

In your first 3–12 months, we’ll look for: 

Foundational prototype – A working proof-of-concept LLM pipeline that ingests our data and demonstrates baseline malicious-intent detection. 

Dataset excellence – Delivery of a set of rigorously labelled examples and clear documentation of labelling guidelines. 

Experiment library – A concise playbook of tried-and-tested techniques (what worked, what didn’t) with key performance insights. 

Vision milestones – Regular demos showing steady feature and accuracy improvements toward our “generic malicious-intent LLM” goal. 

Why Proofpoint 

Protecting people is at the heart of our award-winning cybersecurity solutions, and the people who work here are the key to our success.  We’re a customer-focused and driven-to-win organisation with leading-edge products. We are an inclusive, diverse, multinational company that believes in culture fit, but more importantly ‘culture-add’, and we strongly encourage people from all walks of life to apply. 

We believe in hiring the best and the brightest to help cultivate our culture of collaboration and appreciation. Apply today and explore your future at Proofpoint! #LifeAtProofpoint. 

#LI-Hybrid

Why Proofpoint? At Proofpoint, we believe that an exceptional career experience includes a comprehensive compensation and benefits package. Here are just a few reasons you’ll love working with us:

• Competitive compensation

• Comprehensive benefits

• Learning & Development: We are committed to the growth and development of our team members, offering a range of programs including leadership and professional development workshops, stretch project assignments, and mentoring opportunities to help employees reach their full potential.

• Flexible work environment: [Remote options, hybrid schedules, flexible hours, etc.].

• 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 accessibility@proofpoint.com. How to Apply Interested? Submit your application here https://www.proofpoint.com/us/company/careers. We can’t wait to hear from you!