Prerequisites
You will need to obtain the source code from Git.
Once this is done, you will need Maven 2 (minimum is Maven 2.2.1) to build the project. The dependencies required for building and constructing IzPack are automatically downloaded by Maven over the Internet.
Do not be worried if your first build takes ages while "Maven downloads the whole Internet" 
Run the build
To run a complete build, just do "mvn install" in the root of the project directory.
If all tests success, an IzPack installer is produced in izpack-dist/target/izpack-dist-version-izpack.jar
IDE support
We do not provide IDE-specific project files. We won't add them back to the source code either. Instead, everything is on Maven.
IntelliJ IDEA
IntelliJ IDEA provides out-of-the box Maven integration, meaning that a pom.xml can directly serve as a project file.
The open source / community edition of IntelliJ IDEA has all the features you need for hacking on IzPack, so it is a potentially good choice to let yourself go and try it. Seriously.
Eclipse
Some Eclipse plugins (such as m2eclipse) provide Maven integration.
Otherwise you can use the Eclipse Maven plugin to generate project files for you:
mvn eclipse:eclipse
For your projects to build in Eclipse, you will need to tweak the Eclipse configuration to add a build variable called M2_REPO, which points to your local Maven repository (usually ~/.m2/repository). Otherwise you can also use a specific Maven goal for that.
Newer versions of Eclipse (4.X) in particular with m2e (Also working with older versions of Eclipse 3.8 for example) instead of m2eclipse will work without any need to do mvn eclipse:eclipse. Just import the project from the root into Eclipse via import->Maven Project.
For code style formatting, use this profile and import it to Eclipse: Preferences -> Java -> Code Style -> Formatter -> Import...Â
Netbeans
Netbeans is a friend of Maven too!