While I would never do a take-home assignment for a job, I think your expectations are out of line with the current buyers market that has hundreds or thousands

While I would never do a take-home assignment for a job, I think your expectations are out of line with the current buyers market that has hundreds or thousands of applications for every position. Your solution is the same old thing thousands of others could produce. They want more than a programmer that knows some languages, tools and libraries. I think they might give you 10 more minutes of their consideration if you simply produced a command-line program in Go that used sockets to talk protocols to servers.