Listen to MDN Web Docs

CastReader reads Mozilla Developer Network docs aloud — API references, tutorials, browser guides — while code examples and compat tables stay silent on screen.

100% FreeAPIs · Tutorials · GuidesCode Examples Announced40+ Languages
developer.mozilla.org / Web/API/IntersectionObserver
OpenIntersectionObserver · Web API · 概述
kevin-merge added labels `bug` `high-priority` · 3h ago
KMDN contributorscommented 2h ago

我追到了 token-bucket 实现的问题 —— Redis INCR 与过期重置不是原子操作, 高并发下两个请求都认为自己拿到了最后一个 token。修复要么用 Lua 脚本, 要么改用带 TTL 保护的 INCRBY 重写。

rate-limiter.ts · 4 additions, 1 deletion
- await redis.incr(key);
+ await redis.eval(TOKEN_BUCKET_LUA, 1, key, now);
1.5x

只读 MDN 文档 — 跳过代码示例和浏览器兼容性表

How CastReader Works with MDN

Built for catching up on web standards hands-free

API Reference

🔊 Hear the Description, Skip the Signature

MDN API pages lead with a description paragraph, then signatures, then examples. CastReader reads the description in full — that's the part you usually want. Signatures and example code blocks get announced briefly.

API description first

Browser Compat Tables Skipped

No 'Chrome 57 · Firefox 55 · Safari 12.1' Read Aloud

MDN pages end with browser-compatibility tables. Reading those as a sentence is useless. CastReader skips the compat table — stays visible on screen for quick scanning.

Compat tables skipped

Tutorials in Order

Step-by-Step Guides Narrated Sequentially

MDN's learning-area tutorials are multi-page, step-by-step guides. CastReader walks through them in order — pause between pages, auto-advance when you click next. Useful for refreshers during a commute.

Tutorial sequencing

Multi-Language Docs

Works on MDN Translations

MDN is translated into many languages — French, Spanish, Japanese, Chinese, Korean. CastReader detects the locale from the page URL and uses a native voice for each. No manual setting.

Multi-language docs

Frequently Asked Questions

Everything you need to know about listening to MDN with CastReader

Does MDN have a built-in read-aloud feature?

No. CastReader adds one for free on every MDN Web Docs page.

Does it read code examples?

No — spelling out JavaScript character-by-character is useless. CastReader announces 'code example, JavaScript, N lines' and skips the content. Surrounding prose reads naturally.

Does it work on older MDN (wiki) pages?

MDN transitioned from wiki to markdown-based Yari in 2021. CastReader works on the modern Yari structure. Old wiki archives usually redirect to Yari pages.

Does it skip the MDN sidebar navigation?

Yes. Tree navigation, 'In this article' table of contents, and 'Related pages' widgets are skipped. You hear just the documentation body.

Is it free?

Completely free. No API key, no usage limits, no account required.

Start Listening Now

Completely free. Install and start listening to MDN Web Docs.