Weld Extensions is a library of Generally Useful Stuff (tm), particularly if you are developing an application based on CDI (JSR-299 Java Contexts and Dependency Injection), or a CDI based library or framework.

This guide is split into three parts. Part I, “Extensions and Utilities for Developers” details extensions and utilities which are likely to be of use to any developer using CDI; Part II, “Utilities for Framework Authors” describes utilities which are likely to be of use to developers writing libraries and frameworks that work with CDI; Part III, “Configuration Extensions for Framework Authors” discusses extensions which can be used to implement configuration for a framework