No offense but even the readme is way too long and complicated. And the project itself seems like too much.
I often see people applying make this same mistake with their CV. They'll have a 5 page long incredibly overfilled CV with whatever they ever worked on. Instead, just make it one single clear and concise page so that the recruiter can quickly assess your selling point relevant to the position. They don't have time for all this so why would you?
I apologize if the tone in my comment was not the nicest.
You should know your worth as an employee. If a company asks for too much you must have the ability to stop yourself from working for an entire week with no compensation.
I wouldn’t say you’re at fault for delivering. You are at fault of not delivering a concise solution that uses least elements possible and has a nice clean fast-to-read readme, one setup script or docker file or whatever.
And tbh the result is just a solution (ignoring all the issues of is this terminal inspired and is email backend as a service acceptable choice) - looks generic, nothing interesting besides a super long proposal and super long readme to achieve nothing special honestly. Just a solution checking the boxes. Probably one of many. That’s why probably wasn’t selected.
TL;DR
1. Be more concise in messaging and documentation
2. Do something more than just the working solution esp if they mention brownie points for cool stuff in the task description
I often see people applying make this same mistake with their CV. They'll have a 5 page long incredibly overfilled CV with whatever they ever worked on. Instead, just make it one single clear and concise page so that the recruiter can quickly assess your selling point relevant to the position. They don't have time for all this so why would you?