The purpose of LibreProg is to provide a full set of free and open source assets for anyone to use in their old-school Minecraft projects. We primarily target Beta 1.7.3.
The textures were created while loosely referencing the original textures, mainly for layout purposes. All colors were eyeballed or done from memory.
The app McPerlin was used for a few textures. A few were then tweaked slightly with Aseprite, though LibreSprite can also be used.
In any way you want! Though for ease to access we recommend sticking to the tools that're already in use.