I have been contacted by the HR of the company, 3 stages were announced: Engineering Manager Interview, Test Task and final round (I guess technical). Test task was supposed for 4 hours of work strictly, they sent a requirements list, I have implemented them fully, spent 4 hours and as a feedback I got: "The reason is that we believe your solution was not good enough compared to others in the process.". I did tried to get anything else, some particularities, but HR simply ghosted me.