If you use more than one keyboard with a similar keymap, you might see the benefit in being able to share code between them. Create your own folder in users/ named the same as your keymap (ideally your github username, <name>) with the following structure:
/users/<name>/(added to the path automatically)readme.mdrules.mk(included automatically)<name>.h(optional)<name>.c(optional)
<name>.c will need to be added to the SRC in rules.mk like this:
SRC += <name>.c
Additional files may be added in the same way - it's recommended you have one named <name>.c/.h though.
All this only happens when you build a keymap named <name>, like this:
make planck:<name>
For example,
make planck:jack
Will include the /users/jack/ folder in the path, along with /users/jack/rules.mk.
Please include authorship (your name, github username, email), and optionally a license that's GPL compatible.
For a brief example, checkout /users/_example/ until we have more reasonable and useful examples.