• Make sure Java 7 is installed

• Install Typesafe Activator version 1.2.x and ensure the activator binary is in $PATH

• Run the server

$ activator run
[...]

--- (Running the application from SBT, auto-reloading is enabled) ---

[info] play - Listening for HTTP on /0:0:0:0:0:0:0:0:9000

(Server started, use Ctrl+D to stop and go back to the console...)

• Install node.js and npm.
• cd javascript/
• npm run watch

The npm run watch command will do a npm install if needed, and run the gulp watch task immediately afterwards. In order to make switching between different branches faster, we use a script to store all node_modules folders into .node_cache and then symlink the folder for the current branch to node_modules.

When using IntelliJ or WebStorm, be sure to enable JSX harmony (available in IntelliJ 14 and WebStorm 9) as JavaScript language version to properly support react templates.

You might get an error message during npm install from gyp because the installed (default) Python version is too recent (sic!):

gyp ERR! stack Error: Python executable "python" is v3.4.2, which is not supported by gyp.                                                                                                                 

In this case just set the correct (installed!) Python binary before running npm install:

npm config set python python2.7

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