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# Michael O'Toole
Data Staff Engineer building zero-downtime infrastructure at scale.

## About

Michael O'Toole builds and migrates data platforms at Trade Republic. Over the past decade, he has focused on evolving infrastructure without taking systems offline.

His work centers on open lakehouse architectures and seamless engine transitions. Recently, his team swapped a 620 TB data warehouse at runtime by building a custom proxy with in-flight SQL transpilation, allowing them to migrate query-by-query with zero consumer changes.

Outside of data engineering, Michael plays in the band TwoFoxOut.



## Past Sessions

### World Congress 2026 Europe · July 8, 2026
Berlin, Germany
- [Swapping a Data Warehouse at Runtime: Zero-Downtime Migration Without Changing a Single Client](https://www.wearedevelopers.com/videos/100311-swapping-a-data-warehouse-at-runtime-zero-downtime-migration-without-changing-a-single-client) · 30 min · 🎥 Watch recording



## Videos

- [Swapping a Data Warehouse at Runtime: Zero-Downtime Migration Without Changing a Single Client](https://www.wearedevelopers.com/videos/100311-swapping-a-data-warehouse-at-runtime-zero-downtime-migration-without-changing-a-single-client) · Max Fischer, Michael O'Toole


## Links

- [LinkedIn](https://www.linkedin.com/in/michael-o-toole-6a1695100/)