You won’t be able to work on bundled packages as you normally do.
Firstly, the keymap module is loaded by the
keymap-extensions file and not through the general package loading (see here), this mean that to work your own version you’ll have to hack this line to load it from your own project directory, I didn’t try it but there’s chance that you may eventually have to compile coffee to js yourself (dunno when coffeescript loading occurs during the Atom boot sequence).
Secondly, The error you encounter is due to the fact that since the keymap package is loaded in its own way it just expose the
KeymapManager class and not an Atom module (with
serialize methods), but since you have forked it into the
.atom/packages directory it’s considered as a package to load and loaded as any other package, expecting an
You should first move your fork elsewhere then use a hacked version of the
keymap-extensions file in order to load your project instead.
I guess @kevinsawicki or @ProbablyCorey could give us more insight on how to edit the bundled packages in a cleaner way than this.