FyreVM is Textfyre's interpreter library for the Glulx virtual machine. The library was written by Jesse McGrew in C#, which can be compiled for .NET/Mono or Silverlight, so FyreVM can run on Windows, Linux, and Mac OS X. Customized applications based on FyreVM are shipped with Textfyre's commercial games, and the library is also available under a shared source license.
The interpreter implements a "channel" based I/O system instead of Glk, so it is only compatible with games that were compiled with FyreVM in mind. Inform 7 games can be made FyreVM-aware simply by including an extension. The channel system allows parts of the game output such as score, hints, dialogue options, and prompt to be routed to a user interface layout customized for the particular game.