Karol Pysiak
Machine Learning Scientist at Visa
Warsaw, Masovian Voivodeship, Poland
Summary
👤
Senior🎓
Top SchoolKarol Pysiak is a Machine Learning Scientist with eight years of hands-on experience applying data science to fraud prevention in e-commerce, currently contributing ML expertise at Visa from Warsaw. He combines a formal MEng in Data Science with strong Python and SQL skills, and practical exposure to R, Java and Rust, enabling rapid prototyping and production model maintenance. His background includes training and operating anti-fraud models, building in-house Python tooling, and delivering ETL and API integrations—skills that make him as comfortable with clean code and automation as with experimental research. Colleagues describe him as a data-savvy problem solver who treats analytics like detective work, often finding pragmatic hacks that unlock value beyond standard model improvements.
8 years of coding experience
2 years of employment as a software developer
Warsaw University of TechnologyVI Liceum Ogólnokształcące im. Jana Kochanowskiego w Radomiu
English, Polish, German
Github Skills (10)
genetic9
genetic-algorithm8
javascript8
css8
react8
api7
python5
scikit5
machine-learning5
scikit-learn4
Programming languages (5)
Github contributions (5)
pysiakk/CaseStudies2019S
Feb 2019 - Jun 2019
Warsztaty Badawcze na MiNI Zima 2018/2019
Contributions:26 PRs, 30 pushes in 3 months
javascript
pysiakk/TechnikiWizualizacjiDanych2018
Oct 2018 - Jan 2019
Strona przedmiotu Techniki Wizualizacji Danych na wydziale MiNI PW
Contributions:16 PRs, 19 pushes in 3 months
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