IO.js 2.2.1 发布，现已提供下载。
值得关注的变化如下：
http: reverts the removal of an undocumented client property on client connections, this property is being used in the wild, most notably by request which is used by npm. (Michaël Zasso) #1852.
IO.js 是为 V8 引擎编写的基于事件 IO 的实现。
构建要求：
* `gcc` and `g++` 4.8 or newer, or
* `clang` and `clang++` 3.3 or newer
* Python 2.6 or 2.7
* GNU Make 3.81 or newer
* libexecinfo (FreeBSD and OpenBSD only)
软件详情：https://github.com/nodejs/io.js/blob/master/CHANGELOG.md
下载地址：https://github.com/nodejs/io.js/archive/v2.2.1.zip
来自:开源中国社区
