Why Undefined is the most popular user on Thingiverse

I recently signed up for Thingiverse and noticed it was just a buggy nightmare. I tried uploading my first design a few weeks ago, but it seems to just be stuck in limbo. It shows that I have successfully uploaded one design uploaded, but designs appear on my design page. I have no way to find it, edit it, or share it. It’s just stuck in the ether.

The most interesting bug I noticed though was that I was mysteriously following a user I’ve never heard of. Their username was Undefined and they had only uploaded to the site once back in 2014. You might think the site just automatically makes you follow some random user when you sign up, but I don’t think that was their intention.

It turns out that Undefined is easily the most popular user on Thingiverse, with nearly 5 times more followers than any other account.

I also noticed other users asking why they were “forced” to follow Undefined.

Some of y’all big brains may have already figured this out, but it appears that Undefined’s popularity is due to a bug in the database. For instance if a new user is following=0, the system sees that as an undefined number, and results in the user following Undefined.

A quick search on the Wayback Machine shows that Undefined had 5 followers in 2017, so this bug started sometime in the past four years and 130,000 users have signed up since it was introduced.

I’m officially adding “Undefined” to my list of clever usernames to grab on future sites.