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+*********
+Mopidy.js
+*********
+
+This is the source for the JavaScript library that is installed as a part of
+Mopidy's HTTP frontend. The library makes Mopidy's core API available from the
+browser, using JSON-RPC messages over a WebSocket to communicate with Mopidy.
+
+
+Getting it
+==========
+
+Regular and minified versions of Mopidy.js, ready for use, is installed
+together with Mopidy. When the HTTP frontend is running, the files are
+available at:
+
+- http://localhost:6680/mopidy/mopidy.js
+- http://localhost:6680/mopidy/mopidy.min.js
+
+You may need to adjust hostname and port for your local setup.
+
+In the source repo, you can find the files at:
+
+- ``mopidy/frontends/http/data/mopidy.js``
+- ``mopidy/frontends/http/data/mopidy.min.js``
+
+
+Building from source
+====================
+
+1. Install `Node.js <http://nodejs.org/>`_ and npm. There is a PPA if you're
+   running Ubuntu::
+
+       sudo apt-get install python-software-properties
+       sudo add-apt-repository ppa:chris-lea/node.js
+       sudo apt-get update
+       sudo apt-get install nodejs npm
+
+2. Assuming you install from PPA, setup your ``NODE_PATH`` environment variable
+   to include ``/usr/lib/node_modules``. Add the following to your
+   ``~/.bashrc`` or equivalent::
+
+       export NODE_PATH=/usr/lib/node_modules:$NODE_PATH
+
+3. Install `Buster.js <http://busterjs.org/>`_ and `Grunt
+   <http://gruntjs.com/>`_ globally (or locally, and make sure you get their
+   binaries on your ``PATH``)::
+
+       sudo npm -g install buster grunt
+
+4. Install the grunt-buster Grunt plugin locally, when in the ``js/`` dir::
+
+       cd js/
+       npm install grunt-buster
+
+5. Run Grunt to lint, test, concatenate, and minify the source::
+
+       grunt
+
+   The files in ``../mopidy/frontends/http/data/`` should now be up to date.
+
+
+Development tips
+================
+
+If you're coding on the JavaScript library, you should know about ``grunt
+watch``. It lints and tests the code every time you save a file.