```ruby
class FirefoxNightly < Cask
  url 'https://ftp.mozilla.org/pub/mozilla.org/firefox/nightly/latest-trunk/firefox-29.0a1.en-US.mac.dmg'
  homepage 'http://nightly.mozilla.org/'
  version '29.0a1'
  no_checksum
  link 'FirefoxNightly.app'
end
```

Update Firefox Nightly version from 29 to 30
user
```ruby
class FirefoxNightly < Cask
  url 'http://ftp.mozilla.org/pub/mozilla.org/firefox/nightly/latest-trunk/firefox-30.0a1.en-US.mac.dmg'
  homepage 'http://nightly.mozilla.org/'
  version '30.0a1'
  no_checksum
  link 'FirefoxNightly.app'
end
```
assistant