*`:valid_extensions => %w{js coffee}` to only trigger `run_on_change` events for files with these extensions. Forces Guard to re-run all tests when any other matched file changes.
* All other options from `Jasmine::Headless::Runner`: (see the [list of available options](https://github.com/johnbintz/jasmine-headless-webkit/blob/master/lib/jasmine/headless/options.rb#L11A))
If your code required Jammit or ERB templates, which aren't directly supported by `jasmine-headledd-webkit`,
use [`guard-rails-assets`](https://github.com/dnagir/guard-rails-assets) chained in before `guard-jasmine-headless-webkit` to precompile your application
Do the same for Jammit, using [`guard-jammit`](http://github.com/guard/guard-jammit).
### `guard-jammit` and Jammit >= 0.6.0
Jammit >= 0.6.0 changed how it determines the Rails environment. Use [my fork of `guard-jammit`](http://github.com/johnbintz/guard-jammit) until it's fixed upstream.