Senior Data Scientist - Tax Senior

The opportunity:

EY's GDS IST and TTT team members work side-by-side with the firm's partners, clients and tax technical subject matter experts to develop and incorporate technology solutions that enhance value-add, improve efficiencies and enable our clients with disruptive and market leading tools supporting Tax.

GDS IST and TTT team works closely with clients and professionals in the following areas: Federal Business Tax Services, Partnership Compliance, Corporate Compliance, Indirect Tax Services, Human Capital, and Internal Tax Services. GDS Tax Technology provides solution architecture, application development, testing and maintenance support to the global TAX service line both on a pro-active basis and in response to specific requests.

EY is currently seeking Senior to join our Tax Technology practice.

Your key responsibilities:

• Apply machine learning techniques to deliver actionable insights
• Own end-to-end model development in Python, including data exploration, feature engineering, training, validation, and scoring on structured and unstructured data
• Design and build systems that mine massive datasets and structure/ engineer it to be usable for machine learning models and to apply AI/Machine Learning technology to solve real-world problems
• Apply standard statistical methods, simulation models and statistical programming as needed
• Collaborate closely with business users and analysts to translate requirements into AI/ML solutions and present outcomes clearly
• Manage stakeholders and mentor team members in Machine Learning, AI, and best practices
• Design and implement Generative AI-enabled solutions such as AI agents, APIs, and intelligent interfaces, integrating with enterprise GenAI platforms (Azure OpenAI / Azure AI Foundry)
• Hands-on experience in LLM fine tuning and optimization, including parameter efficient tuning techniques and systematic evaluation of model quality, latency, and cost in production environments
• Strong expertise in production grade prompt and GenAI system design, including prompt templating, chaining, RAG pipelines, guardrails, and reliability patterns for scalable enterprise deployments

Skills and attributes for success:

• An overall experience of 5+ years of which 3+ years of hands-on work experience in Machine Learning and Artificial Intelligence
• Strong hands-on experience with ML/AI techniques including regression, decision trees, random forests, classification, clustering, NLP/NLG, deep learning, neural networks, and ARIMA
• Proven experience delivering end-to-end ML projects from development to production
• Expert proficiency in Python, with strong programming, algorithmic, and database skills
• Strong understanding of Generative AI and LLM technologies, including prompt engineering and enterprise LLM integration

To qualify for the role, you must have:

• Master's degree in Statistics/Mathematics from a reputed college OR Bachelors / Master's degree in Science/ Engineering / MCA.
• Hands-on involvement across the design, development, testing, and deployment of AI/ML solutions
• Tax application experience

Ideally, you'll also have:

• Exposure to cloud (Azure, AWS) would be good to have.
• Strong verbal and written communication skills.

What we look for:

• A Team of people with commercial acumen, technical experience and enthusiasm to learn new things in this fast-moving environment
• An opportunity to be a part of market-leading, multi-disciplinary team of 1400+ professionals, in the only integrated global transaction business worldwide.
• Opportunities to work with EY TAS practices globally with leading businesses across a range of industries