Developer experience (DevX) usability (new article in API doc course)

I added an article called 'Developer experience (DevX) usability' to my API doc course. Usability can be roughly divided into at least three different areas: (1) Usability with physical products, (2) Usability with code products, and (3) Usability with documentation. Few usability researchers venture into usability with code products because it’s much less clear how to assess the usability of code. But make no mistake, usability is just as much in play with code products for developers as with physical products or products with GUIs.