You can work with code outside of the Factor source tree by adding additional directories to the list of vocabulary roots.

There are three ways of doing this.

The first way is to use an environment variable. Factor looks at the FACTOR_ROOTS environment variable for a list of : -separated paths (on Unix) or a list of ; -separated paths (on Windows).

The second way is to create a configuration file. You can list additional vocabulary roots in a file that Factor reads at startup:
Additional vocabulary roots file

Finally, you can add vocabulary roots by calling a word from your .factor-rc file (see Startup initialization file ):

add-vocab-root ( root -- )