Those of us old enough to remember the Twitpocalypse of 2009 know how close Twitter came to utter destruction. Not that close, it turned out. Surprisingly, it seems that bloggers and journalists alike made it sound like a much bigger problem than it was, much like the Y2K bug before it.
The problem was that tweet IDs used 32-bit numbers, i.e. only two billion or so tweets could be tracked. It may have seemed an unfathomable number when Twitter was created, but the site quickly grew out of it.
As the number of tweets quickly approached the maximum number of tweets that could be tracked, there was a risk of it all coming crumbling down.
Now, perhaps to avoid the Return of the Twitpocalypse, Twitter is making the same changes to the user IDs and switching over to 64-bit IDs.
You'd think that 2,147,483,647 IDs would be enough for Twitter, there are only seven billion people on Earth. Facebook only has one billion active users and probably less than two billion registered users.
But maybe Twitter is feeling optimistic. Or maybe it has gotten wind that we're about to make contact with an alien civilization, which could and should lead to a huge influx of new Twitter users.
Well, actually, Twitter currently uses signed 32-bit integers for IDs, giving it a pool of 2,147,483,647 possible users. And, surprisingly or not, it's now approaching that and will most likely surpass the number this year.
Twitter could simply switch to unsigned 32-bit integers, to double the number of potential users, but those would be used up in a few years anyway. So Twitter is moving to signed 64-bit numbers, for some nine billion billion potential users.
If you're a developer, this should interest you as it could affect some or even most apps. You can find out more here.