Hamza Harkous profile

$ Hamza Harkous

Senior Staff Research Scientist at Google

About Me

I am a Senior Staff Research Scientist at Google, where I lead the core synthetic data framework. Recently, I've focused on building agentic, self-improving pipelines for data and environment synthesis. I thrive on taking ideas from zero to scale, owning every step from concept to production.

Featured Projects

Selected research and systems I've built.

Google Simula

2024 – Present

Teaching AI models requires massive amounts of high-quality data, but generating it manually is impossible.

Simple automated prompting causes AI to create repetitive, low-quality data. I co-founded Simula with Benoit Seguin to solve this. We designed a programmable framework that independently controls data diversity, complexity, and quality without human intervention.

We scaled Simula into Google's primary multimodal data synthesis engine. It is now used by over 2,500 Googlers, was used to generate trillions of tokens, and achieved a 93% user satisfaction score, the highest among all data tools at Google. Used by hundreds of teams, today it is a key enabler for the Gemma ecosystem, provides the primary synthetic data backbone for Gemini safety classifiers, powers production user protection features like AI-powered scam detection, and extends much further across frontier AI applications and data use cases.

2,500+
Active Googlers
Trillions
Tokens Generated
93%
Satisfaction Score

Google Google Checks

2020 – 2023

Mobile apps often promise one thing in their privacy policy but do something completely different in their code.

Auditing this manually is impossible. I led the ML strategy and built the core AI systems that were fundamental to launching Google Checks (an Area 120 project). I architected the end-to-end ML pipeline: starting from continued in-domain pre-training on over 1 million policies, training high-capacity T5 11B teacher models, building custom datasets, and distilling them into significantly smaller models.

This ML architecture scaled the system for production serving, allowing it to recognize 70+ legal compliance tags with high precision. Checks launched globally as Google's automated compliance platform, helping developers verify their apps before release.

Press & Official Launches

“Google's Area 120 debuts Checks, an AI-powered privacy compliance solution for mobile apps.”

TechCrunch (2022 Debut) Read full article

Google Hark

2020 – 2022

Users write millions of app reviews daily, but finding genuine complaints in that unstructured noise is like finding a needle in a haystack.

In 2021, we were building specialized LLMs for user feedback. I designed a deep learning pipeline that reads and understands colloquial user complaints, mapping them directly into formal categories.

I scaled Hark, launching Hark's Model Service to power feedback triaging across Google. This became a core analysis engine processing hundreds of thousands of messages and reducing triaging cycle time by 2X. I also drove efficiency gains through distillation, distilling to ~20x smaller models to meet strict QPS requirements. We published the core research at IEEE S&P 2022.

Amazon DataTuner

2019

Turning structured data into natural language without hallucinating facts was a persistent challenge in conversational AI.

In 2019, neural text generation was prone to fabricating facts, and production conversational systems still relied heavily on rigid, hand-crafted templates. At Amazon, I created and led DataTuner to mitigate this hallucination problem end-to-end. We decoupled fluency from factual accuracy: fine-tuning a GPT-2 model to generate diverse, fluent candidate descriptions directly from structured records, paired with a specialized RoBERTa semantic fidelity classifier that audited each candidate to catch omissions or hallucinated details.

By separating generation from semantic verification, we achieved state-of-the-art semantic accuracy across standard data-to-text benchmarks (WebNLG and Cleaned E2E) without relying on dataset-specific heuristics. We published the system at COLING 2020 and open-sourced the framework, which was featured by Amazon Science for its principled approach to faithful text generation.

EPFL Polisis & PriBot

2017 – 2018

Privacy policies are notoriously long, vague, and filled with legalese that nobody reads (and still are).

During my PhD at EPFL in 2017, we helped democratize the use of deep learning for privacy policies, building the most successful and widely adopted system at the time. I built classifiers that segment complex legal text into standardized practices, and created PriBot, an AI chatbot that answers user questions about privacy policies.

I launched Polisis and PriBot as public web services, and the technology was later licensed to major companies, including DuckDuckGo. Over 45,000 users used the tools to inspect privacy agreements. The project was featured in Wired and The Wall Street Journal for making online privacy accessible.

45,000+
Public Users
>100,000
Minutes Spent on App

Experience

Senior Staff Research Scientist

Nov 2025 – Present

Staff Research Scientist

Nov 2023 – Oct 2025

Google

  • Founder & Lead, Simula: Co-founded and grew Google's core synthetic data framework to support over 2,500 Googlers, enabling the generation of >1 billion data items with the highest satisfaction score (93%) across all Google data tools.
  • Creator, Simula Agent: Built the most widely used internal data-generation agent to auto-generate specialized end-to-end Colabs for Googlers.
  • Ecosystem Impact: Serves as a primary data engine for the Gemma family and powers frontier Gemini safety classifiers, evaluations, and features.
  • Wider Impact: Instrumental in public launches like Android Call Scam and Messages Spam detection; integrated into Vertex AI's GenAI Evaluation Service.

Senior Research Scientist

Nov 2021 – Oct 2023

Google

  • Internal Data-Curation Platform: Bootstrapped an internal web platform with active learning and LLM assistance, growing the team to 13 engineers.
  • ML Lead & Architect, Google Checks: Led the ML strategy for Google's AI-powered privacy compliance platform, scaling models to secure thousands of mobile apps.

Research Scientist

Feb 2020 – Oct 2021

Google

  • Google Checks: Architected initial ML models and designed the entire ML pipeline (data labeling, pre-training, and distillation).
  • Hark: Built core ML models and infrastructure for large-scale privacy-feedback analytics processing tens of millions of reviews.

Applied Scientist

Jul 2019 – Jan 2020

Amazon Alexa

  • Developed DATATUNER, a neural data-to-text generation system with state-of-the-art semantic fidelity.

Machine-Learning & Privacy Consultant

Nov 2018 – May 2019

Privately SA

  • Shipped on-device classifiers for hate-speech, toxicity, and emotion detection, launched in a BBC-branded mobile keyboard.

Post-doctoral Researcher

Jul 2017 – Sep 2018

EPFL (LSIR-Lab)

  • Lead author and developer of Polisis, an AI tool analyzing privacy policies for >45,000 users, featured in Wired and WSJ.

Honors & Awards

Transformative Impact Award

Received Google's highest performance rating (top 4%) for the cross-organizational impact of Simula (2024).

3x Google Core Tech Impact Award

Awarded to the top 5% of projects for leading Checks, Simula, and an internal data platform.

Top Code Contributor

#1 Top code contributor at Privacy, Safety, & Security Research in Google (2023-2025).

Caspar Bowden Award (PETS 2017)

International award for outstanding research in privacy enhancing technologies.

Best Ph.D. Thesis Award (2017)

ISSS Excellence Award for best doctoral thesis in Switzerland.

Outstanding Paper Award

Awarded at ACM CODASPY (2017).

Best Dataset Award

Awarded at ACM IMC (2015).

Education

Ph.D. in Computer Science

EPFL (Swiss Federal Institute of Technology)

2017

M.Sc. in Communication Systems

EPFL

B.E. in Computer & Communications Engineering

American University of Beirut

Selected Publications

View All on Scholar

Davidson, T. R., Seguin, B., Bacis, E., Ilharco, C., Harkous, H.

Introduces Simula, reframing synthetic dataset creation as structured mechanism design rather than heuristic prompting, enabling programmable control over data diversity, complexity, and quality.

Gemma Team, Google DeepMind (incl. Harkous, H.)

Contributor to the synthetic data generation pipelines (powered by Simula) used to train Google's open-weights model family.

Zeng, W., Liu, Y., Mullins, R., Peran, L., Fernandez, J., Harkous, H., Narasimhan, K., Proud, D., Kumar, P., Radharapu, B., Sturman, O., Wahltinez, O.

Contributor to the synthetic safety datasets (powered by Simula) used to train and align open-weights content moderation classifiers.

Khandelwal, R., Nayak, A., Harkous, H., Fawaz, K.

Cookie banners use dark patterns to trick you into accepting tracking. CookieEnforcer turns notice rejection into an NLP sequence task: scanning the page to automatically predict and execute the exact clicks needed to decline all tracking cookies.

Harkous, H., Peddinti, S. T., Khandelwal, R., Srivastava, A., Taft, N.

Deep learning pipeline built at Google that reads and categorizes millions of unstructured user complaints to surface hidden privacy issues at scale.

Khandelwal, R., Harkous, H., Fawaz, K.

Privacy settings in modern apps are buried behind confusing, multi-layered menus. PriSEC uses machine learning to navigate settings hierarchies and automatically enforce your privacy choices across mobile and web platforms.

Harkous, H., Groves, I., Saffari, A.

Introduces a two-stage neural generation and semantic reranking architecture that turns structured data into fluent text without hallucinating facts, achieving state-of-the-art accuracy on standard data-to-text benchmarks.

"DataTuner achieves state-of-the-art semantic fidelity without relying on domain-specific heuristics." (Amazon Science)

Linden, T., Khandelwal, R., Harkous, H., Fawaz, K.

Did the GDPR actually change corporate behavior, or just the legal jargon? Using our Polisis deep learning framework, we analyzed thousands of privacy policies before and after the regulation took effect, quantifying how companies really adapted their data practices.

Harkous, H., Fawaz, K., Lebret, R., Schaub, F., Shin, K. G., Aberer, K.

Democratized deep learning for legal text by automatically segmenting complex privacy policies into standardized, human-readable visual flows.

“Polisis: AI reads privacy policies so you don't have to.”

Wired Magazine Read full article

Harkous, H., Aberer, K.

When you install an app, you often expose your friends' data too. We analyzed interdependent privacy leaks across cloud apps and designed smart UI interventions to prevent accidental data leaks.

Harkous, H., Rahman, R., Aberer, K.

Why would a simple PDF converter need access to your microphone and music library? We applied machine learning to mobile app behavior to predict hidden privacy risks, showing how everyday utility apps harvest sensitive data and how users react differently when these risks are clearly explained.