Over the course of a few weeks, I had multiple interviews, including a final-round panel interview and a take-home assignment that took me quite a few hours to complete. The interviews specifically were reasonable and the interviewers were friendly, but they told me I'd be hearing back within a couple of weeks and entirely ignored my follow-up attempts. This is a position I was very qualified for and after multiple rounds of interviews and free work being done in the process, it is extremely unprofessional to completely ghost a candidate and offer no form of feedback or even take a few minutes to let them know that you went with another candidate.