On moving between mastodon instances

On May 2nd, I moved instances for my main Fediverse account. I went from Fosstodon, where I had been since 2020 to C.IM, where I'm now @kzimmermann@c.im. You can take this as an official announcement through this official channel managed solely by me. Nothing else has changed in terms of my online identity, this website and its mirror and my presence elsewhere in the fediverse remain the same. And yes, it's something a lot of people did over the past week or so over an infamous incident rocking the Fediverse and Fosstodon in particular. Perhaps I sound like the late one in that case.

Contrary to what most of those people's reasons, however, my decision to move away is not by any means new. I had been planning a move away from Fosstodon for a few months now, since at least sometime late last year, but simply kept postponing it. I don't quite know why; they do say old habits die hard. Maybe it was me not wanting to lose my almost 1200 followers base, or maybe it was the work required in searching for a new home-sweet-home, or plain ol' laziness (it plagues us all).

But last week, it seemed the time finally came. I did not check on Fedi at all until way late due to the Easter holidays, and when I did, finding context took a while as well. So just a few days ago, I decided on it. I've already created the C.IM account and announced the move on my old one, and now I believe a few people are expecting me to state a reason.

If I had to state it in only one sentence, though, this would be it:

Fosstodon is too big.

Fosstodon has simply become too big for a federated social network node, perhaps an antithesis of what one should be. Of course, Fosstodon isn't alone in this regard; another great counterexample is the original mastodon.social instance.

You may think that userbase size alone can't be too much of a problem, but the consequences are far more reaching than it initially meets the eye. To name a few:

Too big is too expensive

The foremost consequence of having a large instance is the cost. Fosstodon as of this writing requires a whopping 2000+ USD a month to run. While that's not anything like Big Tech datacenter costs, that's still more than a full month's minimum wage in most states in the US, and more than what a managerial-level salary in my country would pay.

And while it's true that more users could mean more donations to keep the instance afloat, it doesn't scale quite linearly. Frankly, the admin team could greatly benefit financially from sending off a large chunk of its user base to other smaller instances that could still afford to run under their planned budgets. I don't know to what proportion does a single user costs an instance, but if Fosstodon could manage to cut the operating costs to about 1000 USD or so, they could run twice as long without any new donations.

This is one of the reasons that I set my posts there to autodelete (I had a LOT of them over the years), and may do so, too, in C.IM.

Too big is too much work

Moderation work is another thing that grows proportionally to the user base, and this has become crystal clear with the last announcement of one of the former admins. As many have pointed out already, Moderation is an unpaid job - also unrecognized, and perhaps an unloved one.

The huge workload is not a recent thing either. Events of peak migration and activities before this one had already caused havoc in the instance that required extraordinary time from the mods (and costs), whom are all volunteers.

It's true that FOSS is all about volunteering, but there must be a limit somewhere. People with full time jobs should not have to moonlight as a thankless and often invisible second line of unpaid work. A smaller and tightly controlled user base would make life a lot easier for the brave mods, and also do wonders for their mental health.

Too big is too risky

"The bigger they are, the harder they fall." It's the same for large instances. The larger they get, the riskier they become to everyone in the federation. How?

First the challenges of moderation may mean that rogue and unpunished users can seemingly wreak havoc in the network, with the entire instance paying for it (the so called fediblocks). They are the minority and the exceptions, sure, but without action taken at them, some admins feel there's no other way to contain them. But when you cut off a large instance, truly a part of the network dies.

And this death can be a little more literal, too: many instances cease to exist "overnight" from simple lack of maintenance or hosters giving up. And when you house tens of thousands of users, what happens to all that data? A large instance like Fosstodon is truly a large responsibility - spreading the risk it carries along other smaller instances is a safer alternative.

History repeating itself

And finally, I must say that this is not the first time I'm seeing this situation.

I previously was part of what was possibly the largest instance of the entire Fediverse 8 or so years ago. For those who weren't around back in the day, Quitter.se was a monster of an instance. Hannes, its (sole?) admin, was swamped with tasks. Sometimes the instance went down because the disk filled up too quickly. Waves of migrants fleeing Twitter caused havoc for moderation, and people closed up registration despite the damage being done. And in the background, something called "mastodon" was slowly dividing the tech powering the federation.

So, amidst this chaos, what happened to Quitter.se? It went down - completely. I can't quite point out when this happened, as I took a big break from the Fediverse between 2019 and 2020, but Quitter.se disappeared some time then, along with its .no and .is neighbors. All those toots, all of those moments deleted forever from an instance that started, peaked, saturated and ultimately collapsed.

I'm not saying this is the fate of Fosstodon, but there are some parallels between the two stories, and having been there in both, I can see them clearly. Fosstodon can do better, and can start right in this moment of turbulence.

So, where to?

The new Fosstodon admin team surely has a big task in its hands. And I can do my part to help by offloading my content somewhere else less crowded and warning people of the dangers of centralizing too much content in a federation.

I know that by moving to C.IM I'm still not solving the problem, just mitigating it a little bit. The truth is that, for real federation to happen here, I would need to roll up my sleeves and host my own - and that is something I've started to consider more seriously lately. Previously, I only considered Pleroma as hostable in my home server (a Raspberry Pi), as it's a more lightweight alternative while still remaining compatible with the original Mastodon.

More recently, however, alternatives for single-user instances have been getting some traction, chiefly with the SNAC2 project, completely written in C, single-user, no database and super lightweight. I feel that this is a strong candidate for me to try out - I just need to learn a little more about how to set up reverse proxies with Apache.

I'm thankful for Mike and Kev, and of course the dream team of admins that kept the instance running all these years for their efforts and dedication. But things changed lately, and it's time to go. As I depart from Fosstodon, I only look back to see the good times I spent there, and wish it good luck with the things to come.

Talk to you from @kzimmermann@c.im!

Last updated on 05/05/25