// Staff Machine Learning Engineer @ Zscaler

Hi, I'm Vishanth.

  • 5+ years in ML & software
  • M.S. UCLA
  • B.Tech NIT Trichy

I build & fine-tune AI guardrails against jailbreaks.

Staff Machine Learning Engineer at Zscaler, leading ML R&D for AI Guard. I build and fine-tune guardrail models that stop jailbreaks and prompt injection, and I optimise GPU inference for 2× throughput at half the latency. Previously Cornami, Disney and Citi.

Vishanth Hari Raj Balasubramanian
Now: AI Guard ML R&D
📍 San Jose, California
ex-Citi · Disney · Cornami
~$2M Saved per year through inference optimisation
2× Requests per second after GPU optimisation
50% Lower inference latency
70B+ Parameter LLMs optimised on DGX H100

01 · About

Making LLMs safe and fast.

I'm a machine learning engineer working where model research meets production systems. At Zscaler I build and fine-tune the AI guardrail models in AI Guard, which stop jailbreak and prompt-injection attacks before they reach an LLM. I also make those models fast and cheap at scale: my GPU inference optimisations doubled throughput, halved latency and save roughly $2M a year.

Before that I built and benchmarked inference engines for frontier open models (Llama 4, DeepSeek V3/R1) on DGX H100 at Cornami. I ran causal-inference research on payments at Disney, built RAG products at traversaal.ai, and spent two years building AIOps systems at Citi.

I hold an MS in Business Analytics (Data Science) from UCLA Anderson and a B.Tech from NIT Trichy, so I care as much about the business impact as the model metrics.

🛡️

AI Guardrails & Security

I build and fine-tune AI guardrail models that detect jailbreaks, prompt injection and data leakage in Zscaler's AI Guard.

⚡

Inference Optimisation

GPU optimisation with TensorRT, ONNX and vLLM: 2× RPS, ~50% lower latency and ~$2M/year saved.

🧩

Distributed Serving

Tensor & data parallelism, FSDP, KV caching, flash attention and quantization for 70B+ models.

🔁

MLOps

Taking models from research notebooks to reliable, monitored production systems.

02 · Experience

Where I've worked

Click a role to expand the details.

  1. Zscaler

    San Jose, CA

    Staff Machine Learning Engineer Oct 2026 – Present
    • Leading the AI Guard ML R&D initiative, Zscaler’s product that protects LLM applications
    • Build and fine-tune AI guardrail models that detect jailbreak and prompt-injection attacks (encoder/decoder fine-tuning, LoRA)
    • GPU inference optimisation (TensorRT, ONNX) that delivered 2× requests per second and ~50% lower latency, saving ~$2M per year
    • Benchmarking GPUs, including AMD, for self-hosting and optimising ML models
    Senior Machine Learning Engineer Dec 2025 – Oct 2026
    • Researched and developed state-of-the-art detectors for prompt injection, jailbreaks and LLM data leakage by fine-tuning encoder and decoder models
    • Scaled and optimised model inference with ONNX, TensorRT and vLLM on GPUs/TPUs
    • Built MLOps for the AI Guard detectors, taking them from research to production
    • LLM Security
    • Fine-tuning
    • TensorRT
    • ONNX
    • vLLM
    • MLOps
  2. Cornami, Inc.

    San Jose, CA

    AI/ML Software Engineer Feb 2025 – Dec 2025
    • Developed and validated LLM engines for Llama 4, DeepSeek V3 / R1 and Llama 3.3 70B, optimising inference with KV cache, flash attention, quantization, tensor and data parallelism
    • Benchmarked models across TensorRT-LLM, vLLM, llama.cpp, Hugging Face and Ollama, turning performance data into engineering and business recommendations
    • Researched inference strategies for in-house Fractal cores and ran 70B+ models on DGX H100 with distributed techniques (TP, FSDP)
    • LLM Inference
    • DGX H100
    • TensorRT-LLM
    • vLLM
    • FSDP
  3. The Walt Disney Company

    Los Angeles, CA

    Data Scientist, ML Research (Co-op) Sep 2024 – Dec 2024
    • Built a causal inference model measuring the impact of each payment provider by region, optimising payment processing and processor fees, reducing costs by 10%
    • Engineered ML models for churn, interchange fees, payment failures and chargebacks
    • Executive KPI dashboard over a 10-billion-row payments pipeline; optimised Snowflake data models and ETL
    • Causal Inference
    • Snowflake
    • Experimentation
  4. traversaal.ai

    Los Angeles, CA

    Machine Learning Engineer Jun 2024 – Aug 2024
    • Built an enterprise multimodal RAG chatbot (images and slides via OCR) with semantic search for traversaal-pro
    • Designed the end-to-end ingestion pipeline (upload → S3 → embeddings → Qdrant) with retrieval, ranking and auth
    • Fine-tuned Llama models for ranking and retrieval; semantic chunking gave 20% better retrieval accuracy
    • Shipped FastAPI services on AWS as API-as-a-Service for clients
    • RAG
    • LangChain
    • FastAPI
    • Qdrant
    • AWS
  5. UCLA

    Los Angeles, CA

    Graduate Teaching & Research Assistant Jan 2024 – Nov 2024
    • Built open-source statistics libraries for bioscience (power analysis, hypothesis testing, resampling), published as resamp on PyPI
    • Teaching assistant for LS 40 Statistics in Bioscience and MGMT 264A Market Research; grader for NLP in Social Science
    • Open Source
    • Statistics
    • Teaching
  6. Citi

    Chennai, India

    Software Engineer 2, AI/ML Innovation Jul 2022 – Sep 2023
    • Tech Innovation Manager for the APAC–EMEA Business Command Center and HNI team at Citi Global Wealth
    • Built ML-driven bots and dashboards (NLP, regression, text mining) to predict and monitor major incidents, saving ~$250K per year
    • Centralised monitoring that reduced downtime by 10%; sentiment-analysis dashboard for the Citibank app
    Software Engineer Jul 2021 – Jul 2022
    • Tech lead at the AIOps Innovation Lab, where I designed the stack (Angular, Node.js, Flask) and Jenkins CI/CD, and set up production infrastructure
    • Integrated Splunk, ServiceNow and IBM Cognos via REST into a central pipeline for incident forecasting dashboards
    • Introduced Agile/Scrum SDLC, saving 100+ person-hours

    🏆 Gold Gratitude Award · Bronze & Copper Gratitude Awards · Client Obsession Award · Bravo Award

    • AIOps
    • NLP
    • Full-stack
    • CI/CD
  7. VEvolve Software

    Tamil Nadu, India

    Machine Learning Engineer (Intern) May 2020 – Aug 2020
    • ML models (text mining, web scraping, random forests) to assess PHP application security vulnerabilities, generating a $30K revenue share
    • Cybersecurity
    • ML
  8. Concordia University, John Molson School of Business

    Montréal, Canada (remote)

    MITACS Globalink Research Intern Apr 2020 – Jul 2020
    • Built a heuristic assortment-optimisation model with Prof. Satyaveer, increasing modelled profit by 6% for Walmart Canada
    • Optimisation
    • Research
  9. IIT Madras

    Chennai, India

    Summer Research Intern, Data Analysis May 2019 – Jul 2019
    • MATLAB data-analysis model for a single-cylinder Gasoline Direct Injection engine at the NCCRD lab, detecting abnormalities in engine parameters
    • Research
    • MATLAB

03 · Projects

Things I've built

PyPI ↗

resamp: Statistics for Bioscience

Open-source Python library for bootstrapping, resampling, power analysis and hypothesis testing, used in UCLA's LS 40 Statistics in Bioscience.

  • Python
  • Statistics
  • PyPI
GitHub ↗

LLM Recommender

Recommends the right LLM for a prompt, using vector search over embeddings built from GitHub, Hugging Face, OpenAI and Twitter APIs.

  • Embeddings
  • Vector Search
  • APIs
Live demo ↗

RAG Semantic Search Engine

End-to-end retrieval-augmented generation system with a metadata index and semantic chunking for accurate document search.

  • RAG
  • Semantic Chunking
  • Hugging Face
GitHub ↗

Multimodal GAN for Fake Detection

97.59% accuracy

Multimodal GAN combining ResNet image features and BERT text features to detect fake data. Top 1% of the class.

  • GAN
  • ResNet
  • BERT
GitHub ↗

MobileNet Image Classification

92% accuracy

MobileNet CNN classifying COCO images for the presence of people, with data augmentation and efficiency tuning. Top 1% of the class.

  • CNN
  • MobileNet
  • COCO
GitHub ↗

Denoising Autoencoder

0.003 MSE

Encoder–decoder architecture for denoising and reconstruction, with MLflow-driven hyperparameter tuning.

  • Autoencoder
  • MLflow
GitHub ↗

RNN Weather Forecasting

91.19% accuracy

Custom recurrent network predicting temperature from historical weather, with time-series feature engineering.

  • RNN
  • Time Series
Thesis ↗

Defect Detection with Deep Learning

Image-recognition model for automated defect detection, replacing manual inspection. Undergraduate thesis.

  • Computer Vision
  • Thesis

04 · Skills

Toolbox

LLMs & Machine Learning

  • PyTorch
  • TensorFlow
  • Hugging Face Transformers
  • LoRA / Fine-tuning
  • LangChain
  • RAG
  • scikit-learn
  • Causal Inference

Inference & Serving

  • TensorRT
  • TensorRT-LLM
  • ONNX Runtime
  • vLLM
  • llama.cpp
  • Ollama
  • Tensor Parallelism
  • FSDP
  • Quantization
  • NVIDIA DGX H100

Engineering & MLOps

  • Python
  • C++
  • SQL
  • FastAPI
  • Flask
  • Node.js
  • React
  • Angular
  • Docker
  • AWS
  • Azure
  • Jenkins CI/CD
  • Git

Data & Analytics

  • Spark
  • Snowflake
  • PostgreSQL / pgvector
  • Qdrant
  • Tableau
  • Power BI
  • Splunk
  • R
  • MATLAB

05 · Education & Recognition

Learning never stops

Sep 2023 – Dec 2024

UCLA Anderson School of Management

🏅 #1 Public University in the US · U.S. News & World Report (2026)

MS, Business Analytics (Data Science)

Machine Learning, Advanced ML, Optimisation, A/B Testing, Data Management, Market Analytics

Jul 2017 – Jun 2021

National Institute of Technology, Tiruchirappalli

🏅 #9 Engineering Institute in India · NIRF 2025 · Top-ranked NIT

B.Tech, Production Engineering · Minor in Computer Science

GPA 9.1 / 10 · Data Structures & Algorithms, Operating Systems, DBMS, Computer Networks, Operations Research

Certifications

  • Amazon Web Services: Machine Learning
  • Machine Learning with Python: Foundations
  • Digital Transformation: BCG & University of Virginia
  • Lean Six Sigma Green Belt (ICGB)
  • HackerRank: Problem Solving

Honors & Awards

  • MITACS Globalink Research Scholar
  • ISB Young Leadership Program Scholar
  • Citi Gold Gratitude Award
  • JEE Advanced rank holder
  • National Science Olympiad
  • NIT Trichy Institute Award

Languages

English · Tamil · Hindi

06 · Contact

Let's build something together.

I'm always happy to talk about LLM security, inference optimisation and applied ML, whether that's collaborating, speaking or just swapping ideas.