I don't know how much existing technology was used, but the feature set sounds quite expansive for 6 weeks of development. Seems like the guy must be a pretty good developer. Aside from the HN shilling, it sounds like the launch marketing was done well.
But then a few surprisingly bad bits: "we had a long heart to heart about 3 weeks after launch". 3 weeks? Just how quickly were they expecting success? Followed by "I assumed that the way I worked on projects (remotely over SSH or SFTP) was how everyone set up their projects" which suggests they did all this without even the slightest bit of market research.
I wish the team good luck in the future. It seems like some smart people made some strangely simple mistakes, but I bet they've got a great chance to be successful in the future.