uh so a purpose part uh as we mentioned in the previous slides uh is about fulfilling the business goals about getting the right information uh to the right side uh usability and constraints this again can be also covered depending on your technology stack and standards you could already have this covered with some standard that you use so for example in recorder we use a json api standard which i'll mention later in the talk and also give some examples and this helped us a lot to really think about the important stuff