For the first series of Material Programming Workshops, we made a forked version of the CMU Knitout Visualiser tool to provide a visualisation interface that would allow students to write knitting code using the knitout-frontend tools, add common features like a waste section, and export directly to the kcode format.
For more information on how to use this tool, please see the guide here, and for more information about the design process, there is a write-up here.