Mooix, which presumably stands for MOO (for/within/integrated with) UNIX, is a type of MUD server, descendent of MOO, that utilizes a fairly unique paradigm for both the developer and user, both of which I will detail here.

It is extremely tightly integrated with the system. Connections are handled by telnetd, and the interface is basically considered a shell by the system. MUD characters are treated as actual users by the system, with a UNIX username consisting of "m-" followed by the first 5 characters of their selected character name. The database is stored as directories and files, with occasional symlinks.

Any programming or scripting language which is capable of manipulating Mooix's data files can be used to write custom commands, in a similar idea to, say, CGI. Libraries have been created to aid in this for several languages, including Perl, C, Ruby, and bash.

When a character is enabled as a programmer, they basically get the amount of power normally associated with a shell account. They can create and execute files, evaluate perl scripts, and can access a simplified version of a standard UNIX shell, among other benefits. Facilities are provided to edit Mooix scripts or programs (using your favorite editor) from within the MUD, then set them up to be executed when a user types a certain command.

Overall, Mooix provides a very rich and versatile environment for developers, allowing seamless mixing of languages within an object-oriented framework for MUD development. This is probably the best codebase for developers who want maximum flexibility.

As to the player benefits, Mooix has a decent english parsing engine. Where using the normal LambdaMOO MOO server or other codebases you would have to type something like this:

drain mead
tip waiter
1 shilling
open door
go door

Mooix allows for developers to provide for advanced constructs like this:

drain the mead, tip the waiter a shilling, then open and walk out the door

Mooix can determine (or guess) what door you mean by "the" door, and recognizes things like "then" or a comma as dividers between commands. It can also guess with relative accuracy what object you mean when you say "it" in a command.

Besides a rather user-unfriendly login, and the fact that it pretty much requires a character-based telnet client such as Windows Telnet or CRT rather than the line-based ones that most MUDs are designed for such as zMUD or MUSHclient (this could be repaired with relative ease by a developer who cared enough about this problem), overall Mooix provides a much more friendly experience than your average MUD.

It's still in "beta" (though it looks like alpha to me, as plenty of features are still being added with each release), and a bit buggy. It's only tested on Debian Linux (and in fact is included with Debian unstable), and I've never seen it successfully installed on anything else, but it probably only requires minor tweaking to allow it to run on other OSes, or at least other Linux distros.

More importantly, it's somewhat slow and very memory-consuming, due to its reliance on system calls for every conceivable little task. Each user logged in consumes the standard 5MB of memory that a standard account does. This is more of a "codebase of the future" (pretending MUD has a future) than anything that would be practical with most server machines today.

Written in Perl and C by Joey Hess (the same twisted mind that brought us PerlMOO). The site is available at http://mooix.net/, where you can download Mooix (in source code form or as a Debian module), subscribe to get updates about it, and talk on the mailing list.