Are We Decentralized Yet?

This isn't quite right. ATProto has a completely different "shape" so it's hard to make apples-to-apples comparison.

Roughly speaking, you can think of Mastodon as a bunch of little independently hosted copies of Twitter that "email" (loosely speaking) each other to propagate information that isn't on your server. So it's cheap to run a server for a bunch of friends but it's cut off from what's happening in the world. Your identity is tied to your server (that's your webapp), and when you want to follow someone on another server, your server essentially asks that other server to send stuff to yours. This means that by default your view of the network is extremely fragmented — replies, threads, like counts are all desynchronized and partial[1] depending on which server you're looking from and which information is being forwarded to it.

ATProto, on the other hand, is designed with a goal of actually being competitive with centralized services. This means that it's partitioned differently – it's not "many Twitters talking to each other" which is Mastodon's model. Instead, in ATProto, there is a separation of concerns: you have swappable hosting (your hosting is the source of truth for your data like posts, likes, follows, etc) and you have applications (which aggregate data from the former). This might remind you of traditional web: it's like every social media user posts JSON to "their own website" (i.e. hosting) while apps aggregate all that data, similar to how Google Reader might aggregate RSS. As a result, in ATProto, the default behavior is that everyone operates with a shared view of the world — you always see all replies, all comments, all likes are counted, etc. It's not partial by default.

With this difference in mind, "decentralizing" ATProto is sort of multidimensional. In Mastodon, the only primitive is an "instance" — i.e. an entire Twitter-like webapp you can host for your users. But in ATProto, there are multiple decentralized primitives:

- PDS (personal data hosting) is application-agnostic data store. Bluesky's implementation is open source (it uses sqlite database per user). There are also alternative implementations for the same protocol. Bluesky the company does operate the largest ones. However, running a PDS for yourself is extremely cheap (like maybe $1/mo?). It's basically just a structured KV JSON storage organized as a Merkle tree. A bit like Git hosting.

- AppViews are actual "application backends". Bluesky operates the bsky.app appview, i.e. what people know as the Bluesky app. Importantly, in ATProto, there is no reason for everyone to run their own AppView. You can run one (and it costs about $300/mo to run a Bluesky AppView ingesting all data currently on the network in real time if you want to do that). Of course, if you were happy with tradeoffs chosen by Mastodon (partial view of the network, you only see what your servers' users follow), you could run that for a lot cheaper — so that's why I'm saying it's not apples-to-apples. ATProto makes it easy to have an actually cohesive experience on the network but the costs are usually being compared with fragmented experience of Mastodon. ATProto can scale down to Mastodon-like UX (with Mastodon-like costs) but it's just not very appealing when you can have the real thing.

- Relays are things "in between" PDS's and AppViews. Essentially a Relay is just an optimization to avoid many-to-many connections between AppViews and PDS's. A Relay just rebroadcasts updates from all PDS's as a single stream (that AppViews can subscribe to). Running a Relay used to be expensive but it got a lot cheaper since "Sync 1.1" (when a change in protocol allowed Relays to be non-archiving). Now it costs about $30/mo to run a Relay.

So all in all, running PDSs and Relays is cheap. Running full AppViews is more expensive but there's simply no equivalent to that in the Mastodon world because Mastodon is always fragmented[1]. And running a partial AppView (comparable to Mastodon behavior) should be much, much cheaper — but also not very appealing so I don't know anyone who's actually doing that. (It would also require adding a bit of code to filter out the stuff you don't care about.)

[1] Mastodon is adding a workaround for this with on-demand fetching, see https://news.ycombinator.com/item?id=45078133 for my questions about that; in any case, this is limited by what you can do on-demand in a pull-based decentralized system.

The expensive things in ATProto are the Relay (crawls/listens to PDSs to produce the firehose) and the AppView (keeps a DB of all posts/likes/etc to serve users' requests). Expensive at scale anyway; if you want your own small network for hosting non-Bluesky posts (like WhiteWind's longer character limit), the event volume will be manageable.

For a lot of stuff though ATProto is built in a way that you shouldn't have to host your own; you can implement your own algorithmic feed that reads from the Bluesky Relay's firehose, or your own frontend that still gets data from the Bluesky AppView.

One reason Bluesky is so successful is because it doesn't shove decentralisation into the user's face like Mastodon does. The vast majority of people don't know what decentralisation is and don't care to.

I think that far too much effort is put into decentralisation and not enough into good moderation on these platforms.

But since essentially no one is using it doesn’t suggest much avoidance of centralization. These factors are not independent. It’s pretty easy to avoid anything when your total user count is a rounding error compared to the alternatives.

Bluesky's architecture was pretty much dictated by the premise that anyone needs to be able to see any post on the entire system, regardless of whether they have any connections with the author. That algorithmic entertainment-style feeds need to exist. You do need that firehose and other expensive infrastructure for that, there's no going around it.

The fediverse, on the other hand, entirely relies on people following each other. Each server only receives and stores data that is relevant to its users. ActivityPub works like an automated email list management system. You follow someone, they start sending you their updates and forwarding any updates from others that they consider relevant, like replies to their posts.

NNTP is also great but most people can not afford individually to mirror entire binary groups and most ISP's no longer perform this so most people just use commercial news feeds if they want binaries or one of the free NNTP / Usenet providers if they are just using text. People can certainly peer with some of the free providers [1] and probably should to reduce the risk of people being censored. Much like IRC people can create their own little private or semi-private linked NNTP servers to replicate a distributed thread based forum of sorts.

[1] - https://www.eternal-september.org/index.php?showpage=peering

(Never used the fediverse, so zero context here).

> A foreigner visiting Oxford or Cambridge for the first time is shown a number of colleges, libraries, playing fields, museums, scientific departments and administrative offices. He then asks “But where is the University?” .....

"The fediverse" is not a thing. There are many separate sites and the collection of all of them in total may be called "the fediverse", but that is not a thing by itself. They don't even all share a protocol in common. You cannot join the fediverse any more than you can join the game industry or the startup scene. You have to join a specific server, game company or startup (or more than one). And while from the outside you might have heard a lot of "the game industry is cut-throat" or "startups work together to innovate technology", once you are inside one of them, you'll find that it's a lot more fragmented than it at first appeared, and totally incohesive, and although from a bird's eye view it looked like you and your competitor down the hall were both making VR happen, they won't work together with you.

You can think of the golden age of blogs and search as an example of both. Search engines formed a centralized hub with blogs, forums, etc. forming the spokes. For a while that worked well before it was degraded by spam and consolidation of disparate forums etc. into a handful of major platforms (fueled partly be acquisitions).

I wouldn’t be surprised if Facebook tries to eventually capture that data with Threads.

Fediverse is almost straight left, and it's already 690. Straight up would be 5000. This is non-linear scale presented linearly.

Until the platform enshittifies like Reddit and Twitter did.

The very second most people need to think about implementation details, like what instance is connected to what instance and what that means, they're done. It's not like they couldn't understand it if they tried: they don't want to try because they don't care. In fact, they don't want to care.

What they care about is interacting with their friends and family and celebrity personas that amuse them, and also get some news handed to them that fits their world view. They don't want to have a little independent social network-- they want to connect with whoever they want to connect with and access whoever they want to access and any barrier to that makes it worse for them. The centralization is the selling point for a lot of those people. Being at the terminal point in a federated service, as they exist, makes all of that harder. It makes it harder for great reasons but they're reasons that most people don't even want to care about. They trade good, easy experiences with the things that are important to them for things they never wanted and have no interest in learning about. Nerds get a kick out of being on a decentralized social network. Most people absolutely do not care. It's not like they don't want to be: it just doesn't matter to them, so if they have to give literally anything up to achieve that, it's too high of a cost.

It's almost like trying to get people to switch from mobile phones to amateur radio.

In the real world, you can ask people if they would prefer to live in a town with all bespoke mom'n'pop businesses or just a few big box retailers and chain restaurants identical to the ones in the next town over. The intuitive expectation might be that most people would prefer the bespoke stuff because it offers a more personalized service, but it turns out that many people really do want to have the same experience as folks in the next town over. Even among folks who claim to be free thinkers or unique personalities, even among folks who have xenophobia or express a chavinistic sentiment, there is still an impulse to seek the exact same experiences that folks outside of their community are also having. Why is that?

I am sure there are various psychological and perhaps even physiological reasons why people are drawn to homogeneity, but the bigger problem is that bad actors can find ways to exploit these reasons to amass power. Once those actors have the power to shape society, then it becomes a feedback loop where perhaps in the abstract a person might not desire exactly those experiences that are provided by the central authority, but because the structures in society are now pointing toward that being the "best" option, then that's what people come to believe they want.

I suppose the philosophical question is if people come to want to be exploited, is it still okay to exploit them? Personally I think it's not okay. I think it's a worthy goal to present other options. In an ideal world, perhaps there would be structures in society that define open standards that allow people to find the homogeneous experiences they value while still ensuring that no central authority could take ownership over the delivery of those experiences. Perhaps there should be some assurance that those who deliver the experiences aren't also using other levers at their disposal to engineer the desire for those experiences in the first place.

Which is all to say that perhaps social media should be better regulated, and as nerds we might think that one way to do that is build it into the base technology as decentralization or federation. But one would hope that people outside of tech could at least understand the value, since the tech is just a model of real-world systems.

People outside tech very much do care about the effects of centralization, though. They complain about it constantly, in oblique terms.

All the waxing poetic about "social media"? They aren't mad that people talk to each other. They're mad at platforms.

They just don't recognize the root cause of their pain points until they're sufficiently technical.

E-mail is really ingenious. It doesn't even define how to send and receive messages in the same standard. One standard is just for delivering messages; you have to figure out how you're going to receive them separately.

Of course most people have an e-mail address hosted by one of a handful of large companies. But you don't have to. And if you buy your own domain, changing providers is easy. Delete your old mail on the old server, upload it to the new server, people can still contact you the same way they did before.

I'm not on social media, so I don't have any dog in this fight. But all the properties of a good decentralized/federated platform are already there in decades-old protocols.

> Hell, I would even say that threads is the biggest mastodon instance.

So is Truth Social. But they are not federated with the rest.

The chicken and egg problem is that users go where the content is, and content goes where users are.

In reality what this means is that the vast majority of both users and content tend towards a single solution, and that is where there is the least friction, aka the path of least reesistance.

Monetary incentives and various perks (features, first mover advantage, ...) can help but overall it seems to tend towards ease of use.

For users, TikTok is the king for a reason: EVERY SINGLE SWIPE (caps because I want to intentionally put a LOT of emphasis on this) is content that YOU, specifically YOU, are likely interested in. If not, the very next swipe is likely to be what your brain thinks is good, because the algorithm is so good it already knows what you want. Yeah, I know, that's because they spy on their users, whatever, sadly users do not care about that.

BlueSky? Even if you follow specific users, content discovery is so, so much harder. But the main problem is that the vast majority of users, especially new ones, will be subjected to subpar content compared to other platforms.

So why should a new user come back there instead of literally anywhere else? And if there are no users, why put the content there, and if there is no content, there are no users, and so on...

Notice how in all of this the underlying architecture has quite literally no relevance and is nothing but a technical detail.