Building
========

Marionette is built in to Firefox and ships in the official
Firefox binary.  As Marionette is written in [XPCOM] flavoured
JavaScript, you may choose to rely on so called [artifact builds],
which will download pre-compiled Firefox blobs to your computer.
This means you don’t have to compile Firefox locally, but does
come at the cost of having a good internet connection.  To enable
[artifact builds] you may choose ‘Firefox for Desktop Artifact
Mode’ when bootstrapping.

Once you have a clone of [mozilla-unified], you can set up your
development environment by running this command and following the
on-screen instructions:

	% ./mach bootstrap

To perform a regular build, simply do:

	% ./mach build

You can clean out the objdir using this command:

	% ./mach clobber

Occasionally a clean build will be required after you fetch the
latest changes from mozilla-central.  You will find that the the
build will error when this is the case.  To automatically do clean
builds when this happens you may optionally add this line to the
_mozconfig_ file in your top source directory:

	mk_add_options AUTOCLOBBER=1

If you compile Firefox frequently you will also want to enable
[ccache] and [sccache] if you develop on a macOS or Linux system:

	mk_add_options 'export RUSTC_WRAPPER=sccache'
	mk_add_options 'export CCACHE_CPP2=yes'
	ac_add_options --with-ccache

[mozilla-unified]: https://hg.mozilla.org/mozilla-unified/
[artifact builds]: https://developer.mozilla.org/en-US/docs/Mozilla/Developer_guide/Build_Instructions/Artifact_builds
[ccache]: https://ccache.samba.org/
[sccache]: https://github.com/mozilla/sccache