Nightli.es provides automatic nightly builds for Travis CI.
When developing a library, often some components like other libraries or the language interpreter will use the latest available version. This can lead to nasty situations when an upstream component releases a new version that breaks your tests, but you don't find out until your next git push. Nightli.es ensures each project builds at least once every 24 hours so these failures will be caught as soon as possible.
Nightli.es uses the Travis API to get the list of projects you have access to and to kick off builds. Unfortunately Travis' GitHub authentication integration requires that I request all the same permissions as Travis itself. Your GitHub OAuth tokens are never stored server-side, only your Travis API token is stored for use in starting builds via the API.