Bulk process excel to html templates (nodejs, Python, c#/mono)

I have some excel sheets with each row of the excel needing to be converted to html. We will use the columns in the excel to identify the right template to output to and then merge those values to the template. The large body of content in the excel will have formatting. To have the right format go from excel to something we have decided to go with markdown. So in one of the columns you will find markdown representing the majority of the html content. You will want to process to html in the final static output. The excel will also have images for the page. Image will have name relative to a directory. We will grab that image and resize it. Depending on template type will determine the resolution we use. Should be easy in c# but let me know if you chose another program language. I would be open to other things like Python or nodejs if you provide basic webpage to upload zip of exce plus images and output zip of html and images.