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# Peter Kröner
Front-end trainer exploring the weirdest fringes and loopholes of JavaScript.

## About

Peter Kröner is an independent front-end trainer who spends his days reading dry specifications and fighting browser bugs. He teaches developers how web standards actually work under the hood.

Instead of sticking to standard practices, he embraces the weird edges of programming. His presentations uncover JavaScript's most awful legacy features and show how to exploit obscure ECMAScript loopholes to write valid but delightfully chaotic code.



## Past Sessions

### World Congress 2026 Europe · July 8, 2026
Berlin, Germany
- [Extreme Rules Lawyering with the ECMAScript Specifications](https://www.wearedevelopers.com/videos/100116-extreme-rules-lawyering-with-the-ecmascript-specifications) · 30 min · 🎥 Watch recording

### World Congress 2025 · July 9, 2025
Berlin, Germany
- [Best of the Worst – the most awful anti-features in JavaScript, ranked!](https://www.wearedevelopers.com/videos/1451-best-of-the-worst-the-most-awful-anti-features-in-javascript-ranked) · 30 min · 🎥 Watch recording



## Videos

- [Extreme Rules Lawyering with the ECMAScript Specifications](https://www.wearedevelopers.com/videos/100116-extreme-rules-lawyering-with-the-ecmascript-specifications) · Peter Kröner
- [Best of the Worst – the most awful anti-features in JavaScript, ranked!](https://www.wearedevelopers.com/videos/1451-best-of-the-worst-the-most-awful-anti-features-in-javascript-ranked) · Peter Kröner
- [Defeat that legacy monster! Guerilla refactoring with web standards](https://www.wearedevelopers.com/videos/647-defeat-that-legacy-monster-guerilla-refactoring-with-web-standards) · Peter Kröner
- [Where we're going we don't need JavaScript - Programming with Type Annotations](https://www.wearedevelopers.com/videos/455-where-we-re-going-we-don-t-need-javascript-programming-with-type-annotations) · Peter Kröner

## WeAreDevelopers LIVE

- [WeAreDevelopers LIVE – Keeping Up with Styles, Data & More](https://www.wearedevelopers.com/videos/1803-wearedevelopers-live-keeping-up-with-styles-data-more) · Chris Heilmann, Daniel Cranney, Peter Kröner
- [WeAreDevelopers LIVE – Spicy Vanilla Web, CSS Magic & More](https://www.wearedevelopers.com/videos/1753-wearedevelopers-live-spicy-vanilla-web-css-magic-more) · Chris Heilmann, Daniel Cranney, Peter Kröner


## Links

- [LinkedIn](https://www.linkedin.com/in/peterkroener/)
- [Blog](https://peterkroener.de)