Weld, the JSR-299 Reference Implementation (RI), is being developed as part of the Seam project. You can download the latest community release of Weld from the download page. Information about the Weld source code repository and instructions about how to obtain and build the source can be found on the same page. Weld provides a complete SPI allowing Java EE containers such as JBoss AS and GlassFish to use Weld as their built-in CDI implementation. Weld also runs in servlet engines like Tomcat and Jetty, or even in a plain Java SE environment. Weld comes with an extensive library of examples, which are a great starting point from which to learn CDI.