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# Best of the Worst – the most awful anti-features in JavaScript, ranked!


- **Date:** Thursday, Jul 10, 2025
- **Time:** 14:50–15:20 (30 min)
- **Room:** Stage 11
- **Event:** World Congress 2025
- **Tags:** design patterns, frontend, javascript, web standards

## Recording

[Watch recording](https://www.wearedevelopers.com/videos/1451-best-of-the-worst-the-most-awful-anti-features-in-javascript-ranked)

## Description

Browser, browser on the wall, who's got the worst features of them all? JavaScript of course!

This session takes a close look at the most awful features in JavaScript and the DOM, how they work and why they are still part of today's web standards. We explore the reasons for continued browser support of even the most broken features from the cretaceous period, how bad decisions from the 1990s still haunt JavaScript's syntax today and which absurd hacks from ancient history are still being re-purposed even today.

Apart from sheer shock and/or entertainment value, even the most awful anti-features in JavaScript are actually worth learning about. Sometimes they are important constraints for the continued evolution of the JavaScript standard, and sometimes they are simply the only way to solve (extremely specific) programming challenges. If you ever wanted to know why JavaScript works and looks like it does or just like to gawk at some rather... exotic code, this is the session for you!

## Speaker

### [Peter Kröner](https://www.wearedevelopers.com/@peter-kroner)

Webtechnologie-Erklärbär


## Related talks at this congress

- [Friend or Foe? TypeScript Security Fallacies](https://www.wearedevelopers.com/events/world-congress-2025/sessions/694-friend-or-foe) — Liran Tal
- [Code Red: When Your Tools Turn Against You ](https://www.wearedevelopers.com/events/world-congress-2025/sessions/510-code-red-when-your) — Aaron Bray, Julian Totzek-Hallhuber
- [Lessons learned from observing a billion API requests](https://www.wearedevelopers.com/events/world-congress-2025/sessions/845-lessons-learned-from) — Pratim Bhosale
- [Advanced Micro Frontends: Multi-Version and Multi-Framework Scenarios](https://www.wearedevelopers.com/events/world-congress-2025/sessions/501-advanced-micro) — Manfred Steyer