Requirements

Minimum System Requirements

Running the Game

Hardware:

Shader Model 2.0 capable GPU (Radeon 9500+ / GeForce FX5200+ / GMA X3100+)
1GB Free Hard Drive Space
512MB RAM (the game itself uses ~100MB)
Sound
3 Button Mouse
Network Card (desirable)
Display capable of at least 1024×768

Software Dependencies:

Windows Vista, 7, 8 (x86 and x64)

• NET Framework >= 4.0

Mac OS X 10.6

• Mono Framework >= 3.2
• XQuartz

Ubuntu 14.04

• mono-gmcs
• cli-common-dev
• libgl1-mesa-glx
• libopenal1
• libfreetype6
• libsdl2
• liblua5.1

openSUSE 13.1

• mono-devel
• openal-soft
• freetype2
• SDL2
• liblua5_1

Development

Technically anything with git and a text editor, but you probably want at least the requirements to run the game, plus:

Software:

Git
A C# compiler (Mono’s CGC, xbuild/msbuild)
An IDE like MonoDevelop/Xamarin Studio, Visual Studio (Express)

Mac OS X

Install fink, then install glib2-shlibs and glib2-dev. (possibly not the first, try just glib2-dev and pkgconfig)