Sebastian Kaczmarczyk
Alternative Data Analyst/Decision Scientist
Experience
Alternative Data Analyst/Decision Scientist
Balyasny Asset Management
- Led the development of three internal data/AI products for Portfolio Manager teams, created PoCs, defined requirements, and coordinated engineering to deliver production-ready tools.
- Owned relationships with hundreds of internal stakeholders, ensuring efficient data access, clear prioritization, and smooth collaboration across Tech, Data, and PM teams.
- Managed a 7-person engineering team, overseeing sprint planning, resource allocation, and workflow optimization to remove bottlenecks.
- Built several AI-driven utilities to enhance internal research and data handling efficiency.
Senior Data Scientist
J.P. Morgan Chase
- Worked closely with Marketing, Customer Experience, and Finance to turn business problems into clear technical requirements.
- Delivered a customer experience chatbot using modern NLP/LLM approaches, improving internal support workflows.
- Built multiple data-driven tools and analyses supporting European business units.
- Collaborated with cross-functional partners to clarify needs, validate assumptions, and deploy solutions into day-to-day use.
Senior Data Analyst
RTB House
- Reduced Account Manager analysis workload by ~25% through process automation and improved reporting.
- Designed an internal forecasting tool and built dashboards used across APAC stakeholders.
- Led a project using NLP on customer audio/video interactions to flag churn risks, guiding AM teams toward retention opportunities.
- Enhanced operational efficiency through systematic reporting and tool development.
Business Analyst
Bain
- Supported due diligence projects and operational improvements for clients.
- Worked on UI/UX optimization and A/B testing initiatives.
- Conducted analysis across customer behavior, segmentation, and product performance.
Investment Analyst
Sunfish Partners
- Conducted in-depth fundamental analysis of potential investments.
- Tracked and managed deal flow pipeline.
- Developed and implemented marketing strategies to enhance brand awareness, attract potential customers or investors, and increase market share.
Funding Consultant
Grantland
- Performed market and business-side analytics.
- Led the development of comprehensive business plans, including defining business objectives, target markets, competitive strategies, and financial projections.
Summary
AI & data product leader with experience delivering products end-to-end in high-stakes financial environments. I combine technical understanding (LLMs, data pipelines, alt-data, cloud) with strong product ownership, cross-functional communication, and team leadership.
I’ve managed engineering teams, gathered requirements from senior investment professionals, built PoCs, and driven products from concept to production — improving workflows, reducing operational bottlenecks, and enabling revenue-generating insights.
I bring a mix that’s hard to find: I understand the technical side well enough to build prototypes and guide engineers, but I also think like an operator who cares about adoption, deadlines, and real impact. I’ve already shipped AI/data products in complex financial environments, managed teams, and worked with demanding stakeholders. I know how to turn a vague idea into a working solution, and I take full ownership from the first discussion to the moment a tool is actually used. If you need someone who can deliver fast, communicate clearly, and raise the bar for how product is run — that’s what I do best.
Skills
Core Skills
- Product Ownership & Delivery
- Stakeholder Management
- Requirements Gathering
- Team Leadership
- Ai/llm Product Development
- Data Products
- Operational Efficiency
- Cloud (Aws / Gcp)
- Sql
- Python
Tech Skills
- Python
- Git
- Data Pipelines & Automation
- Dashboarding (Tableau/ Looker)
- Llms & Nlp
Languages
Education
Polish-Japanase Institute of Information Technology
MSc in Data Science · Data Science · Warsaw, Poland · 4.7/5
Warsaw School of Economics (SGH)
MSc in Finance and Accounting · Finance and Accounting · Warsaw, Poland · 4.6/5
The University of Sheffield
LLB Law · Law · Sheffield, United Kingdom · 1st Class Honours Degree
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