I went through an initial phone screening and then was given a weeklong coding challenge. They provided me the test on a Friday evening on July 1, before a long weekend, and told me that I had a week to complete the challenge (an initially frustrating request, as I then spent my holiday weekend working on a code challenge).
After completing part 1 of the code challenge, I submitted my solution.
They then sent me part 2 of the code challenge. They did not reply to my emails about how long I had to finish this part of the code challenge. Likewise, this part was not very clear, and the guidelines provided did not seem to match very well the actual desire of those I was interviewing.
The response they provided when declining to move on was a very terse paragraph saying my skills didn't align, with no further explanation of what was wrong with the solution I provided.