MUSH Software
Maintainers and developers of MUSH servers have traditionally shared ideas with one another, so most MUSH servers include concepts or code developed originally in other servers. There is particular interest in ensuring that common MUSHcode features work similarly across servers.
PennMUSH, TinyMUSH, and TinyMUX are open-source. Rhost is free, but not open-source. Some enthusiasts may exclude one or more of the above on the basis of distribution method, name, or parentage, but all are free-form MUSH servers. Differences in the software tend to focus more on the administrative and/or softcode side (slightly different function syntax; or different functions altogether; more, or less, administrative controls). The set of commands that players use to interface to the game are essentially standard amongst servers bearing the appellation 'MUSH'.
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