The recruiter reached out to me through LinkedIn asking if I was interested in the role and after talking for a while it did sound like they were trying to solve some interesting challenges. I agreed to move forward and they gave me an assignment which they wanted done in the next few days. I actually had a certification the next day which I was preparing for and I said it might be hard for me to complete in the next few days given I was working full time and the certification. I asked the recruiter to send me the assignment in 2 days after my certification and I should be able to work the weekend to get that done. Nevertheless, the recruiter sent the assignment right after the call (probably a red flag that the recruiter didn't listen to what you said). At this point, I was mostly concentrating on my certification and the next day the recruiter replied asking to acknowledge the email and the assignment. Fast forward couple days after my certification, I started looking at the assignment and looked pretty simple enough to add a database and expose the aggregation results. I wanted to check if they had a choice of database and if they wanted the results to be shown in the UI. They replied any database and visualization not required. Not only did I spend the weekend to do that, but also added visualizations for the aggregations and sent the assignment a day before the deadline. I thought it was a good solution. After a couple days the recruiter reached out to me and says they are not moving forward with my application because I "did not follow the instructions properly"! I thanked them for the opportunity and wished them good luck in their search and asked for feedback for me as to which instruction were not followed. No reply so far. Anyways, I don't think I would have consider interviewing with them in the future.