Yep, that was one of my projects. The github code is out of date. The installer for v2.9 also contains the source code.
https://sourceforge.net/projects/geep-jeez/files/I believe I left the project is a fully working state and suitable for all my needs, but its been 7 years. I just downloaded the installer on my last Windows 7 machine, and it still runs. I'm sure with the right version of TDM-GCC installed, the system would work as it should. I do recall being able to compile all Jesus Script effects at that time, but I'm sure JS has evolved.
There was some work done on a LADSPA interface (Linux Audio Developer's Simple Plugin) as well, which at the least achieved the generation of at least one working plugin for Audacity under Linux. But, since I didn't need it, no more work was done.
I do recall issues with making sure a specific version of TDM-GCC was used. But, that could have been due to me using Windows XP at the time.
Anyway, you are more that welcome to do as you please with the code. I wrote it for myself, so I could knock up VST's quickly. I'm not sure such a program is needed anymore. But, at the time I thought it was cool.
I guess, these days I'd either stick with JS or LUA to prototype audio effects, then re-code in C++.
But, its there if you so wish to play with it. Cheers.