Well, you're also describing Ardour (with the proviso that we don't allow scripts to much on the GUI side of things). Access to the "object model" from Lua is e

Well, you're also describing Ardour (with the proviso that we don't allow scripts to much on the GUI side of things). Access to the "object model" from Lua is extremely wide-ranging, and since Ardour itself is open source, you can add whatever other access you need or want rather easily.