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 since May 2010 the library is also available under the MIT license. The source code is now hosted at SourceForge.
The interpreter impcllements the Channel IO 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 a library extension, allowing them to run in both FyreVM and Glulx interpreters using Glk. 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.