You will need to upgrade Node.js to [6.x+](https://github.com/nodejs/node/blob/master/doc/changelogs/CHANGELOG_V6.md). If using [nvm](https://github.com/creationix/nvm) (you should be!) the process will go something like this:
Newly written code will use ES6 and a lot of code has started the migration process. Of note is the `MenuModule` class. If you have created a mod that inherits from `MenuModule`, you will need to upgrade your class to ES6.
If you have overridden or made additions to archivers in your `config.hjson` you will need to update them. See [Archive Configuration](docs/archive.md) and `core/config.js`
As 0.0.4-alpha contains file bases, you'll want to create a suitable configuration if you wish to use the feature. See [File Base Configuration](docs/file_base.md).