First off this game looks fantastic! I give big props to the developers for leaving their jobs to do what they love.
I’m curious though about what programming languages are being used to create the game and what other tools/engines are being used, like Unity or something else?
From what I’ve read and/or heard, it appears to be custom written in C++ and Lua, with a heavily modified version of Horde3D (with custom nodes, shaders, etc. for rendering.) Correct if I’m wrong if there is anybody out there who can find an official statement or has more knowledge.
Base framework is C++11 IIRC. Everything else is scripted with Lua, which is what the players will have access to when they want to do any in-depth modding.
Models are made with a software called Qubicle, and animated in 3dStudioMax (although in the livestream it was mentioned that this was just the dev’s personal preference).
And it uses JSON, or something like that.
This has been answered several times. The collated q&a should be the first place you check. 
JSON is used to save the animations, indeed.
@henryforprez Hey there, this is taken form the collated Q & A:
Engine/ Programs used ---------------------“Qubicle Constructor.”
“We wrote our own engine in C++ and Open GL.”.
“The game engine is written in C++ with Lua for scripting. We use Horde3d for rendering with a few custom node types, custom extensions, and lots of our own shaders.”
Also, extra little bit of info:
“We use Qubicle for all the voxel art. Stonehearth comsumes .qb files natively and our resource file format is just JSON, so it’s really easy to get new art assets into the game. We’re using 3DSMax for rigging and animation, but the animation file format is, again, just JSON.”
Hope that helps!
@henryforprez It’s located here: [urlhttp://discourse.stonehearth.net/t/collated-q-a-information-and-suggestions/73/]Collated Q & A[/url].
Bookmark that! Excellent Q & A by the way Geoffers, I don’t believe I gave my thanks for creating that.
Also, I believe a Kickstarter stretch goal picture re-upload is in order!
$240,000. Amazing what a bunch of random people can do and create when they get together.
@A1UR Thanks for the heads up! Just submitted an essay so I’m good for the rest of the day to add any questions and answers I’ve missed.
Oop, thanks for that, I’ll add it in!
So, erm, I’ve hit the character limit. Turns out it’s 16,000 character’s.
Just a head’s up for you all!
Perhaps make another thread for the q&a and then reserve a few posts for extending it? Would be quite a bit of work but, just an idea! 