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JSJS QuestionsLAB

Built by @kitsunekode. Original questions and explanations by Lydia Hallie.

XProject Repository

Product

  • Questions
  • Progress
  • Release notes
  • Credits

Resources

  • Project Repository
  • Lydia's Original Repo

Question content is based on Lydia Hallie's original 2019 repository, so newer JavaScript language features may not be covered everywhere. Learn more

JSQL · v0.1.7

Credits & Attribution

Built by @kitsunekode, powered by Lydia Hallie's questions.

JS Questions Lab is a creator-built practice product. The original questions and explanations come from Lydia Hallie's javascript-questions. My contribution is the product layer: the interface, runner, visualization, scratchpad, and progress loop that make the material feel more usable in real practice sessions.

This page extends the original credits, it does not replace them. The upstream source references and supported language listing stay preserved below.

@kitsunekodeGitHub profileProject repository

Why I Built It

A strong source deserved a stronger practice surface.

Lydia's repository is one of the best JavaScript references on the internet, but interview prep usually needs a faster loop than reading a long markdown file. I built this so you can answer first, reveal second, run code immediately, and come back with progress that still means something.

This project is also personal proof-of-work. I wanted the site itself to show care: design restraint, faster interactions, better mobile ergonomics, and a clearer sense that someone is actively making the experience better.

What I Added

  • +A focused question library instead of a long README scroll
  • +Worker-based runnable snippets that stay inside the app
  • +Event-loop visualization for runtime-heavy questions
  • +Progress, review cues, bookmarks, and a cleaner practice loop

Original Credits

Thank you to Lydia Hallie for creating and maintaining the source material this experience is built on.

The question content, explanations, and the original educational foundation all belong to that work and its contributors.

The original repo links and the supported language files stay visible here so the source material remains easy to trace back to.

Original repositoryLydia Hallie

Source Integrity

Source file

README.md

Generated

Mar 29, 2026

Current locale

English

Questions

155

Upstream commit

a8b427b

latest

Supported Languages

Preserved from the upstream source.

These translation links come directly from Lydia Hallie's source material and stay part of the credits page so the original language coverage remains visible.

Start practicing
  • 🇺🇸

    English

    en • 155 questions

  • 🇪🇸

    Español

    es • 116 questions

  • 🇫🇷

    Français

    fr • 64 questions

  • 🇩🇪

    Deutsch

    de • 133 questions

  • 🇯🇵

    日本語

    ja • 86 questions

  • 🇧🇷

    Português (BR)

    pt-BR • 80 questions

  • 🇸🇦 العربية
  • 🇪🇬 اللغة العامية
  • 🇧🇦 Bosanski
  • 🇩🇪 Deutsch
  • 🇪🇸 Español
  • 🇫🇷 Français
  • 🇮🇩 Indonesia
  • 🇮🇹 Italiano
  • 🇯🇵 日本語
  • 🇰🇷 한국어
  • 🇳🇱 Nederlands
  • 🇵🇱 Polski
  • 🇧🇷 Português Brasil
  • 🇷o Română
  • 🇷🇺 Русский
  • 🇽🇰 Shqip
  • 🇹🇭 ไทย
  • 🇹🇷 Türkçe
  • 🇺🇦 Українська мова
  • 🇻🇳 Tiếng Việt
  • 🇨🇳 简体中文
  • 🇹🇼 繁體中文