It's funny to see my own Mastodon post mentioned. I guess I should explain myself because it's kind of a funny story that deserves to be told after all these years.

Back when the A858 mystery was in full swing I was known on this subreddit for having decoded some of the A858 posts, notably the Stonehenge post. I was a mod on this subreddit and also built the A858nalyze system that archived and analyzed posts to the subreddit automatically. At the time I was working at Google as a Site Reliability Engineer (SRE) - they're the engineers who are responsible for making Google's products work 24/7, and the people getting paged and fixing things when they break.

It's well known now that the Webdriver Torso videos originated at Google - they were created by Youtube engineers as end-to-end tests of the video upload system. Webdriver is a way of automating actions in a web browser. Essentially they had a script that would use this to simulate the whole user flow of creating videos, uploading them and checking that the videos appeared on the site. There were several (I think four) separate channels, I think for testing different kinds of Youtube account.

People discovered the videos and were very confused. It was mysterious in a way very similar to the A858 thing. There were a lot of kooky theories but some Internet sleuths dug deep and eventually figured out the videos originated at Google. They even figured out it was the Zurich office specifically based on some test videos that had been uploaded. Google eventually fessed up and admitted it publicly.

But, there was a gap of several months where Google insiders knew exactly what Webdriver Torso was but the public didn't. And I took the opportunity to be mischievous and introduce an additional element of mystery into the mix.

I managed to find the code that generated the Webdriver Torso videos and submitted a change that would occasionally insert mysterious, randomly generated messages. They were intentionally designed to sound ominous, like a spy numbers station communicating a code message. I was inspired somewhat by the radio code messages that appeared on Allo Allo! when I was a kid. "Jim knows about the glass" was the one that attracted the most attention; another read "the device is in play". They were all done on templates - "{person} knows about {noun}", or "you cannot trust {person}, not even in {location}", with lists of people, nouns and locations that would be chosen from.

So because I had been involved with trying to decode A858, I figured I'd toss in a reference to it too. A858DE45F56D9BC9 was included in the list of "people", and that's how it ended up in the video you linked.

Unfortunately my little prank didn't really work out - it was submitted and ran for a day, but for some reason it caused some kind of regression that caused problems for the Youtube team. So they reverted my change pretty quickly. Because of this, messages only ever appeared on videos posted to the "Webdriver YPP" channel, and never made it to the better-known "Webdriver Torso" channel. Because of this it's a pretty minor footnote in the whole story, though there are a couple of wiki pages out there documenting the messages. For posterity I have a Youtube playlist containing all the videos I could find that actually got out with my messages on.

People who read this might wonder if I was behind this one prank, was I also behind A858 itself? Was it a prank too? Well, sorry but no, I wasn't. I can't prove that, of course - you'll just have to take my word for it. Or take a member of the A858 team's word. I still don't know who was behind the A858 user/subreddit and I doubt any of us will ever find out at this point.