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+# Apache NetBeans Packager (nbpackage)
+
+`nbpackage` is a command line tool and library for packaging the NetBeans IDE or
+a NetBeans platform application into a native installer or package. It supports
+optional bundling of a Java runtime to make a self-contained application. It is
+inspired by the JDK's `jpackage` tool, but tailored to the needs of the IDE and
+RCP, with a different range of packagers, and some support for cross-platform
+package building.
+
+**nbpackage is still under development.**
+
+## Usage
+
+Run `nbpackage --help` to see options.
+
+While options for the packagers can be set on the command line, the easiest way
+is to use the support for a configuration file in Java Properties format.
+
+Use the `--save-config` option to output all available options, or just the ones
+for a specific packager, to a properties file. Using a separate configuration file
+for each package type is probably the best option. The output file includes
+comments for each available option.
+
+eg. to build an InnoSetup installer, first create the configuration file -
+
+`nbpackage --type windows-innosetup --save-config inno.properties`
+
+Edit the properties file, with package name, customized icons, path to Java
+runtime, etc. As well as the path to the native build tool.
+
+Then build the installer from the IDE / RCP zip using -
+
+`nbpackage --config inno.properties --input <PATH_TO_ZIP>`
+
+Use the `--verbose` option to see the output of the native packaging tools.
+
+`nbpackage` will first build an image - a directory with the correct layout and
+additional files for passing to the packaging tool. It is possible to use the
+`--image-only` and `--input-image` options to perform this in two separate passes
+to allow for customization of the process.
+
+## Supported packagers
+
+Only a few packaging types are supported so far - more to follow, including macOS
+bundles and Linux deb.
+
+### `--type linux-appimage`
+
+Create a Linux [AppImage][appimage]. Requires download of the
+[AppImageTool][appimagetool], making it executable, and adding the path to the
+configuration file.
+
+### `--type windows-innosetup`
+
+Create a Windows [Inno Setup][innosetup] installer. Requires download of the
+installer tools, and adding the path to the `iscc` compiler to the packager
+configuration. See also [further information on the iscc tool][iscc].
+
+Inno Setup works well with Wine for building installers on other OS. Write a short
+shell script that invokes the `iscc` tool via `wine` and use this in the packager
+configuration - eg.
+
+```bash
+#!/bin/sh
+wine C:\\Program\ Files\ \(x86\)\\Inno\ Setup\ 6\\ISCC.exe $1
+```
+
+### `--type zip`
+
+Mainly for debugging purposes, although can be used to bundle an RCP application
+with local runtime. As the IDE launcher does not yet support relative JDK location,
+this is less useful there.
+
+## Building from source
+
+Building `nbpackage` requires Maven and JDK 11+. Building in the IDE or executing
+`mvn package` will build the tool. Output can be found in `target/appassembler`.
+
+Run `./appassembler/bin/nbpackage --help` to check.
+
+[appimage]: https://appimage.org/
+[appimagetool]: https://github.com/AppImage/AppImageKit/releases/
+[innosetup]: https://jrsoftware.org/isinfo.php
+[iscc]: https://jrsoftware.org/ishelp/index.php?topic=compilercmdline
