A number of command line switches can be passed to a bootstrap image to modify the behavior of the resulting image:

-output-image=image	Save the result to image. The default is factor.image.
-no-user-init	Inhibits the running of user initialization files on startup. See Running code on startup.
-include=components...	A list of components to include (see below).
-exclude=components...	A list of components to exclude.
-ui-backend=backend	One of x11, windows, or cocoa. The default is platform-specific.

Bootstrap can load various optional components:

math	Rational and complex number support.
threads	Thread support.
compiler	The compiler.
tools	Terminal-based developer tools.
help	The help system.
handbook	The help handbook.
ui	The graphical user interface.
ui.tools	Graphical developer tools.
io	Non-blocking I/O and networking.

By default, all optional components are loaded. To load all optional components except for a given list, use the -exclude= switch; to only load specified optional components, use the -include=.

For example, to build an image with the compiler but no other components, you could do:

To build an image with everything except for the user interface and graphical tools,

To generate a bootstrap image in the first place, see Bootstrapping new images.