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# Marco Sieben
Software engineer tackling JavaScript's date handling and the Temporal API.

## About

Marco Sieben builds software at andrena objects ag. Since 2016, he has been navigating the quirks of web development, often tackling complex period calculations and frustrating timezone bugs.

His current focus is untangling JavaScript's notorious date handling. He breaks down the new Temporal API, showing frontend developers how to finally retire bulky third-party libraries for temporal math.

When he isn't fighting with datetimes, Marco wonders how humanity managed a 1969 moon landing while native date logic still feels like rocket science.



## Past Sessions

### World Congress 2026 Europe - Virtual Stage · June 30, 2026
Online
- [It's about time! The new Temporal API in JavaScript](https://www.wearedevelopers.com/videos/2009-it-s-about-time-the-new-temporal-api-in-javascript) · 🎥 Watch recording



## Videos

- [It's about time! The new Temporal API in JavaScript](https://www.wearedevelopers.com/videos/2009-it-s-about-time-the-new-temporal-api-in-javascript) · Marco Sieben


## Links

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