CIRCA5000 Software Developer interview questions

There was an initial telephone interview to assess my experience with the requirement of the role. The person I talked to gave a nice introduction about the company and what is required from the role. Then I explained about my experience and it was all good. Then I received a Technical task. It was not a hard task at all so I send it the next day ( I received it on a Thursday and I sent it on Friday). I have not heard anything back until Tuesday and after I sent a reminder only they replied they'll review it. Later that day (today) I got a call saying the task was not up to their standard. The task was to implement a simple api endpoint. The instructions were to get correct responses for given inputs. They had good examples of input and expected output mentioned in the document. The requirement was clear; Put your code on a public source repository (such as GitHub) and give us the URL. That exactly what I did. Also I added authentication to the API which they have not even mentioned and I did the one mentioned as 'BONUS', Test class (had no mention about test classes in the task too!) for testing and a ReadMe file with clear instructions how to run it in local. I added all their sample inputs and outputs in the test class I wrote as data to get expected output. So I obviously asked why it's not 'up to standard' . The feedback I got is; 1. Not writing a test for a function - Yes I didn't write a test for one function, the reason being the tests I wrote was already covering that part. According to them the function had a 'complex' logic in it - I know the definition of complex changes depending on the person but I beg to differ. 2. Not presenting the project as a docker image! Even though I could partially agree with the 1st point this one I cannot agree. The instructions were clear, had to be on github. Now they suddenly require docker image? Also worth mentioning here the role is not devops, its back end dev (not saying back end devs doesn't need to have devops side of knowledge). I have to be clear here; they were not able to give any other reason why they fail my task apart from the above 2. Its up to who ever reading this to decide whether it is fair to fail a backend developer task based on above. I'm not in a position to say whether they are serious about recruitment or not. I read reviews in here today and I saw some similar things happened to other candidates as well. All I want to say is please do some research before applying for any company. If possible ask someone working in that company. Tickr if you're reading this; You must be doing really well in the business side but please give clear instructions to candidates on about your expectations. Don't tell to KISS (Keep it Simple Stupid ) and expect the candidate to meet all your telepathic requirements. Good luck.