Downloading Hirundo 0.8.5 for Mac from our website was free. The program is included in Lifestyle Tools. This free software for Mac OS X was originally designed by Stylemac.
From the developer:
Hirundo is a convenient way to browse and follow the discussions in Swift mailing lists like Swift-Evolution or Swift-Dev. You can even bookmark messages of threads because they contain important information. Read messages from selected authors, search for authors, or even manage favorite authors. You can also sort messages by various properties, including a Rank showcasing the most discussed threads.
You may want to check out more Mac applications, such as Reunion, HanDBase Desktop or S90 ES Total Librarian, which might be related to Hirundo.