PayMongo Software Engineer interview questions

I had two video calls, first with HR to get an overview of my past work experience, skills, and personality/attitude. That was short and pleasant. I was then sent instructions via email on what sort of take-home exercise they expect from me for the next interview step. The instructions were clear enough, and I appreciated that they let you choose whatever language you're comfy with. And lastly, this is also important: a full-stack solution or database connection was NOT required. I thought the exam difficulty was just right and it probably would boil down to code and how I could talk about my solution to my interviewers. I proceeded to the next step (code presentation) after a review, however, I apparently flopped it. It was very frustrating to me that they asked me why I didn't have a database connection even though they specifically stated on their email that it wasn't required. Didn't really live up to their initial email statement about having the freedom to work on a solution that fits your skills. They also didn't send me feedback even though they said they would, and I had to contact them back after two weeks to ask how my application was going. HR responded fast with a rejection email, haha. TL;DR: HR interview is short and sweet. Take-home exam is average but can be improved way more with a narrower scope IMO. Choose your own language/tech stack, but probably best to connect to a database if you're applying for a senior position (or asking for 100K minimum salary). Though honestly, I never understood how it shows "skillz" when you can easily look at a database's documentation to see how it can be connected to your app. PayMongo, if you are expecting something specific from your exam-takers, then narrow down your scope and expectations in your email, please.