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# Nikolai Nikolaev
Data specialist bridging the gap between business goals and IT execution.

## About

Nikolai Nikolaev connects business requirements to IT execution at Eurowings Holidays. He focuses on turning raw data into metrics that actually answer specific organizational questions, rather than relying on out-of-the-box analytics.

He specializes in wrangling massive datasets with Apache Spark. Nikolai teaches other engineers how to build custom, type-safe User-Defined Aggregation Functions (UDAFs) to handle complex metrics that standard tools fail to capture.



## Past Sessions

### World Congress 2025 · July 9, 2025
Berlin, Germany
- [Let's Get Aggregated: Custom UDAFs in Spark  ](https://www.wearedevelopers.com/videos/1649-let-s-get-aggregated-custom-udafs-in-spark) · 30 min · 🎥 Watch recording



## Videos

- [Let's Get Aggregated: Custom UDAFs in Spark  ](https://www.wearedevelopers.com/videos/1649-let-s-get-aggregated-custom-udafs-in-spark) · Nikolai Nikolaev


## Links

- [LinkedIn](https://www.linkedin.com/in/nikolaevn/)