As far as I'm aware, this mod never had its source code released. This code was produced using B3DDecomp on executables that can be obtained on Steam.
The generated code has been slightly modified to disable the server list.
To build this mod, you will need mavless bin (lol what a misnomer) and patch the Large Address Aware flag because this uses too much memory to run without that.
The game is based on the works of the SCP Foundation community (http://www.scp-wiki.net/).
This game and the source code are licensed under Creative Commons Attribution-ShareAlike 3.0 License.