This is great! Ever since I briefly worked with .rmd files in combination with RStudio I had it in the back of my mind that it would be nice to have something like it (but lightweight) for Markdown with Python and pipe the output through Pandoc. Jupyter Notebooks are nice, but it gets hacky to use your own editor and the file format is bad for git diffs. I'm definitely going to give Codebraid a solid try.