I have done this with Google Chrome.
- Get your starred repositories from the GitHub API: https://api.github.com/users/USERNAME/starred?page=1&per_page=100
- Open the Web developer tools in Chrome. Select the pre Tag in the HTML-View and execute this Javascript in the console:
JSON.parse($0.innerText).map(function(repo) { return 'https://github.com/' + repo.full_name + '/releases.atom' }).join('\n')
. This generates a list of the Release-Feed-URLs. - Copy the URL list to http://reader.feedshow.com/goodies/opml/OPMLBuilder-create-opml-from-rss-list.php If you have more than 100 starred repositories, you need repeat step 1 to 3 and increment the page in the URL in step 1 each time.
- Click "Create OPML".
- Save the OPML XML file to disk.
- Import the OPML file into your feedreader (that supports OPML). I used Feedly.