A source code search engine - https://searchcode.com/
Java Source Code Search - http://grepcode.com/

Browser

Web Browser Compatibility Tables - http://www.webbrowsercompatibility.com/

JavaScript

Babel - https://babeljs.io/
ECMAScript compatibility table - https://kangax.github.io/compat-table/es6/

Swift

Swift Language in Chinese - https://github.com/DiveinEdu/swift-language-in-chinese

White House Web API Standards - https://github.com/WhiteHouse/api-standards

三醒的Blog - https://libereco.cn/
快速的java小知识分享 - http://www.javaflush.com/
Yun Notes - http://blog.yunnotes.net/