Senior Data Scientist & AI Engineer

Hi, I'm Sak Nagpal

I build data-driven systems and agentic AI pipelines - turning complex problems into production-ready solutions.

Projects

A selection of production systems, ML pipelines, and side projects

Customer Feedback Intelligence System

LLM-powered complaint classification and routing at scale.

Built and deployed a production LLM-based customer complaint classification and routing system processing 100k+ historical enquiries at Jetstar Airways. Combined the Claude API with KNN clustering to identify complaint categories, achieving 92% classification coverage — replacing a brittle rule-based approach and materially improving routing accuracy and resolution efficiency. Designed a RAG-based architecture integrating internal knowledge sources, evaluating trade-offs across latency, cost, and model performance.

PythonClaude APILightGBMRAGKNN clusteringLangChainSnowflakeMLOps
Generative AINLPLLMsProduction ML

Maintenance Log Classification and Fault Forecasting

NLP pipeline for aircraft maintenance logs with predictive fault detection.

Designed and delivered an NLP pipeline for automated classification of aircraft maintenance and engineering logs at Jetstar Airways, where unclear technician-written entries previously required manual expert review. Extended the system to forecast recurring fault patterns across the fleet — reducing mean time to identify faults by 30% and enabling proactive maintenance scheduling. The system handles noisy, domain-specific language with high accuracy across a diverse range of fault types.

PythonNLTKTF-IDFTextBlobLightGBMSnowflakePower BISkyWise
NLPClassical MLForecastingProduction ML

Operational Knowledge Assistant

Amazon Bedrock-powered internal policy retrieval assistant.

Architected and built an internal LLM-powered knowledge assistant using Amazon Bedrock, trained on operational manuals and staff travel policy documents. The system enables accurate, instant retrieval of policy information — reducing staff onboarding time by over 95% with near-100% accuracy in seat allocation decisions. Built on a RAG architecture with careful chunking and retrieval strategies optimised for long-form policy documents. Currently in final pre-production validation.

Amazon BedrockClaude SonnetStrands AgentsRAGBedrock Knowledge BaseBedrock Data AutomationS3MCPAgentCore GatewayNavitaire NewSkiesPythonDatadog
Generative AIAgentic AIRAGProduction MLAWS

Melbourne Property Research Agent

Agentic AI tool for suburb-level property research and investment analysis.

A fully agentic React + FastAPI application that autonomously researches Melbourne suburbs for property investment decisions. Built on a LangGraph state graph with conditional edges and real-time streaming SSE — the agent selects tools dynamically with visible reasoning steps. Powered by live data sources: property prices and median sale stats from Victorian Valuer General (VGV) sales data, and suburb demographics from the ABS 2021 Census DataPack covering population, median income, household composition, and owner vs. renter split. Price trend queries render an inline Recharts chart directly in the chat UI. A Haiku-based query guardrail classifies and short-circuits irrelevant queries before they reach the agent loop. Amenities integration in progress. Backend deployed on Railway, frontend on Vercel.

PythonFastAPILangGraphClaude APIABS Census DataVGV Sales DataReactViteRechartsRailwayVercel
Agentic AIFull-StackProperty

Customer Segmentation & Risk Modelling

ML-driven segmentation models serving 5M+ retail banking customers.

Led the customer segmentation modelling workstream at ANZ Bank, coordinating analysis across a team of analysts and presenting outcomes directly to senior stakeholders. Designed controlled experiments to evaluate credit risk and segmentation models serving approximately 5 million retail banking customers. Identified feature drift and model degradation patterns that informed quarterly retraining cycles, maintaining accuracy within agreed SLA thresholds.

Pythonscikit-learnSQLTableau
MLExperimentationFinancial Services

Australian Superannuation Calculator

Interactive super growth projector encoding Australian tax rules.

A fully client-side superannuation growth calculator built for Australian professionals. Encodes ATO rules for FY2025–26 including the Superannuation Guarantee rate, concessional contribution caps, Division 293 tax for high earners, and the Low Income Super Tax Offset (LISTO). Features scenario comparison mode, inflation-adjusted projections, a year-by-year breakdown table, and reactive input validation. Built with React, Tailwind CSS, and Chart.js — deployed on Vercel with no backend dependency.

ReactViteTailwind CSSChart.js
Personal FinanceReactData Viz

Writing

Skills & Tools

Technologies I work with in production

AI & Machine Learning
Pythonscikit-learnLLMsRAGPrompt EngineeringClaude APIOpenAI APIAmazon BedrockHugging FaceLangChainspaCyNLTKKNN / Clustering
Data Engineering
SnowflakePySparkSQLSQL ServerETL/ELT PipelinesAWSGCP
Visualisation & Delivery
Power BITableauStreamlitJupyter
ML Engineering
MLOpsModel MonitoringCI/CDContainerisationGitHub Copilot
Certifications
  • SnowPro Core — Snowflake (2025)
  • Master of Data Science — Monash University
  • Bachelor of Technology (CS) — Federation University

Experience

Where I've built and shipped

AI Implementation Lead & Senior Data Scientist

Jetstar Airways|Melbourne, Australia

Oct 2023 – Present

Leading delivery of AI and Generative AI solutions across operations, driving adoption of scalable, production-ready ML systems and mentoring cross-functional teams.

  • Built production LLM complaint classification system processing 100k+ enquiries, achieving 92% classification coverage
  • Delivered NLP pipeline for aircraft maintenance log classification, reducing mean fault identification time by 30%
  • Architected internal knowledge assistant on Amazon Bedrock, reducing staff onboarding time by over 95%
  • Established standardised ML experimentation frameworks, reducing iteration cycles by ~30%
  • Built reusable data and ML pipelines in Snowflake across multiple production use cases

Data Scientist

Australia and New Zealand Bank (ANZ)|Melbourne, Australia

Dec 2019 – Oct 2023

Led customer segmentation modelling and credit risk analysis across ~5M retail banking customers.

  • Led customer segmentation modelling workstream, presenting outcomes to senior business stakeholders
  • Designed controlled experiments evaluating credit risk models serving ~5M retail banking customers
  • Identified feature drift and degradation patterns informing quarterly retraining cycles
  • Built dashboards and analytical tools to communicate insights across cross-functional stakeholders

Data Analyst / Senior Student Systems Analyst

Wesley College|Melbourne, Australia

Dec 2017 – Dec 2019

Analysed large datasets to drive student performance outcomes and automated reporting processes.

  • Identified improvement opportunities contributing to a 15% increase in student performance outcomes
  • Automated reporting processes, improving efficiency across the analytics function

Get in Touch

I'm open to discussing senior data science and AI engineering roles, consulting, or interesting project collaborations. Fill in the form or reach out directly.