"Decentralization" and erasure: Blacksky, Bluesky, and the ATmosphere

Part 3 of I for one welcome Bluesky, the ATmosphere, BTS ARMY, millions of Brazilians, Black Twitter, and sex worker Twitter to the fediverses. Originally written December 2024, epilogue added August 2025.

"As Black users, aka Black Twitter, flee X in unprecedented numbers, a grassroots developer is building what many see as the future of Black social media culture. His platform, Blacksky, gained over 750,000 users in months without venture funding or promotion, operating as an open-source project on the decentralized Bluesky social network."

– Tarik Moody, Could Blacksky emerge as Black Twitter’s spiritual successor on Bluesky?

In the original version of the first post in this series, I said I thought it was obvious that Bluesky and the ATmosphere are decentralized. Okay, fine, it clearly isn't obvious; I was wrong about that part! See the Appendix for a partial list of some of the dozens of interesting perspectives on whether or not the Bluesky social network and the broader ATmosphere (an ecosystem of services and apps built on top of Blueskys Autenticated Transfer Protocol, aka AT Proto).

That said, my conclusion hasn't changed. I still see Bluesky and the ATmosphere as clearly decentralized.

Rudy Fraser's Blacksky, for example, runs three feed generators, a moderation service, and a work-in-progress personal data store (PDS), and is considering implementing their own relay as well. And as Moody notes, the vision for Blacksky "extends beyond any single platform":

"Fraser envisions Blacksky’s open-source technology, as enabling other marginalized communities to build safe spaces online. Already, he’s hosting other communities on Blacksky’s infrastructure while letting them maintain their distinct identities.

“Every time the culture moves to a new app, there’s a Black Twitter, there’s Black TikTok, a Black People Reddit section,” Fraser notes. “What if you keep your community and the interface changes?”"

That sounds pretty darn decentralized to me!

Blacksky is an independent project.
Please join me in supporting them!

It's true that Blacksky also currently relies on some of Bluesky's services. As of December 2024, Bluesky currently runs the only network-wide Relay and the PDSs and AppViews used by 99%+ of the people in the ATmosphere; Bluesky also controls the identity provider, the protocol, and the official Bluesky software When Bluesky's Relay was down for a few hours last week, so was Blacksky (and almost everything in the ATmosphere).

Then again, Blacksky's already building their own PDS; once it's available, people will be able to store their data on a server not under Bluesky's control – and will be able to have an *.blacksky.app handle.

Update, September 2025: Blacksky PDS blacksky.app and hundreds of accounts are now hosted there (including my new primary account at @jdp23.blackcomra.de). The blacksky.community app uses the Blacksky moderation service and has the Blacksky: Trending as the feed for new users (which in turn leverages atproto.africa 🌍 , "One of (if not Thee 1st) from-scratch, full-network relays").

That sure looks decentralized about me.

In Fraser's December 2024 roadmap he talked about possibly doing their own Relay. As Isaiah Thompson notes in Building #Blacksky

"Part of the vision, too, for Blacksky is to become resilient enough to eventually live on its own servers—literally and otherwise."

If the Bluesky Relay and Appview went away (or put in unacceptable new policies), Blacksky could almost certainly get their own up and running – by themselves, or working with some of the communities Fraser is already hosting.

Update, March 2025: Fraser talks more about building "our own independent implementation of Bluesky's underlying technology" and the goal of "trying to create a home for Black users on the network that is safe and self-governable and self-sovereign" and in the TechPolicy.Press Podcast with Justin Hendrix. Blacksky's also working on Cypher, an Appview, with "local-only posts"

So while I agree that today's actually-existing Bluesky and ATmosphere are still largely centralized in some important ways, and that the combination of AT's architecture and Bluesky's initial dominance could well lead to de-facto centralization, my perspective is that focusing only on that ignores the ways that they already are meaningfully decentralized.

Your mileage may vary of course. "Decentralization" means different things to different people, and as Tolulope Oshinowo et al point out in Seeing the Politics of Decentralized Social Media Protocols, different protocols interpret "decentralization" in different ways. As the links in the Appendix highlight, people who are focusing on the (very real) concentration of power in the ATmosphere today, or the potentially-centralizing architecture of AT, find it more useful to describe Bluesky as centralized.

Blacksky has been erased from discussions of Bluesky's decentralization

Regardless of the conclusions people reach, though, what's especially interesting to me is that as far as I can tell, nobody else in the discussion is talking about Blacksky as an actually-existing example of decentralization. What's with that?

The erasure of Blacksky from this discussion is particularly striking because so many people writing about this talk about a goal of decentralization is to create a more equitable distribution of power. Hey wait a second, that's what Blacksky is actually doing! And you don't just take my word for it. Here's what Fraser says in Blacksky: Expressing the Black Everyday in a New Digital Space (Part 3)

"The power in the protocol is that other people (in this case people who aren't me) will be able to build job boards, dating apps, and video streaming(?) social apps and Blacksky will work across all of them on the same infrastructure.

To put it plainly, it will be someone else's job to come up with the next TikTok, the next Reddit, or the next LinkedIn. My only job will be to integrate it into Blacksky (which should be easy) and amplify, protect, and moderate Black content no matter where it is on the network....

Tools like Bluesky and AT Protocol have their own tradeoffs and considerations (what @ntnsndr.in describes as "implicit feudalism" for one) but personally my belief in self-determination extends to my technology use and development. And the opportunity to build out an extensible Black social network that can be controlled by community instead of corporations, that doesn't require being segregated from the broader social space, and reflects the many aspects of the diaspora (not just whatever is trendy at the time or what a corporation is pushing on me) is too important to pass up."

But no. Instead, all the discussions of power distributions are in a deracialized context. Watch whiteness write.

Pay attention, dammit!

"Seize this new technology, all the new technology. Deal with it! ‘Cause we’re not gonna unknow anything anyway. And make that technology act in a desired manner as both a tool and a weapon."

Sister Elaine Brown, quoted in Rudy Fraser's Blacksky: Expressing the Black Everyday in a New Digital Space (Part 3)

"[A]s Blacksky highlights, Bluesky and that ATmosphere are developing new organizations for strong communities and how they interact, complementing the Fediverse's instance-oriented structure. These aren't (yet) as place-oriented as Fediverse instances but it's still useful to think of them as part of the Social Archipelagos ... and new topologies may well emerge.

– me, in From the Fediverse to fediverses, communities, and Social Archipelagos

A lot of the pushback to the idea that Bluesky is decentralized has come from people comparing it to the ActivityPub-based Fediverse. And don't get me wrong: many of the concerns people bring up are worth paying attention to. Bluesky currently dominates the ATmosphere far more than any single entity dominates today's ActivityPub Fediverse. Even if that changes, the AT ecosystem could wind up resembling the web, where Google, Microsoft, and a few other search engines largely control visibility; or email, where Google, Microsoft, and a few other email providers host 95% of personal email accounts. AT Proto is an all-public architecture that's optimized for surveillance capitalism, and includes several choke points that are likely to lead to centralization. And there are plenty of other ways in which Bluesky is problematic as well.

Still, whether or not you're just focusing on decentralization, dismissing Bluesky without even considering Blacksky isn't just erasure, it's also missing out on something very important. Especially for people in the ActivityPub Fediverse – with its long history of whiteness, anti-Blackness, and misogynoir – there's a lot to learn here. More positively, the ActivityPub Fediverse's focus on scoped-visibility complements Bluesky's panoptic all-public architecture, so there's a lot of opportunity for hybrids that combine the Fediverse model of smaller networked communities with Blacksky's innovative approach to community in Bluesky/AT Proto's "big world" flat networks.

But it's really hard to learn from Blacksky if you're pretending it doesn't exist.

So please stop doing that.

And please don't just learn from Blacksky.
Please also support Blacksky!

For more on Blacksky, here's Rudy Fraser's December 2024 Tech Talk – good stuff!

Speaking of erasure ...

At least Blacksky is getting attention in the broader conversation about Bluesky, and Fraser's work is justifiably being credited as playing a huge role in leading to so much of Black Twitter moving to Bluesky. But even though Fraser deserves all the credit in the world for this, he's not the only one who deserves all the credit in the world.

Work by Aveta (aka @aliafonsy.bsky.social) – including their original Black Tech Twitter follow thread as well as inviting so many key Black tweeters to Bluesky in early 2023, and then speaking out strongly against the anti-Blackness on Bluesky – also provided a critical foundation for Black Twitter's move to Bluesky. And unsurprisingly, Aveta has been almost completely erased from the broader narrative. In fact, as far as I know, Bluesky hasn't ever even apologized to Aveta for the shitty stuff that happeend back then – let alone credited these contributions or looked for ways to help get compensation for Aveta and others for all the unpaid work they did to make Bluesky succesful.

What's with that?

Yeah, I know this might seem like a digression from the discussion of decentralization. But it certainly relates to discussions of equitable distribution of power on social networks, and that's what decentralization is supposedly about. Also, there's certainly a parallel between how Blacksky has been erased from discussions of decentralization and how Aveta has been eraased from the broader narrative. And since I mentioned the ActivityPub Fediverse in the previous section, there's also a parallel to how Marcia X's contributions with #Fediblock aren't generally acknowledged. So maybe it's not really that much of a digression after all?

Epilogue: nine months later

Blacksky has continued to progress by leaps and bounds in the months since I first wrote this post, expanding the team and executing on the path that Rudy Fraser laid out in 2024.

• Blacksky is now hosting almost all of their own infrasctructure.
• Hundreds of people have set up accounts on the blacksky.app and blackskycomra.de PDS (personal data server) – including me.
• The blacksky.community app has the outstanding Blacksky Moderation service enabled by default, and the also-outstanding Blacksky: Trending as the feed for new users instead of Bluesky's crappy Discover feed).
• Behind the scenes, the Blacksky feeds use the Blacksky relay at atproto.africa, which extends relay functionality by including a "mod relay" - and other ATmosphere software is starting to use it as well.

This is what solidarity looks like, part 2 of the series, goes into more detail.

And while Rudy deserves every bit of the credit he's getting for Blacksky's success, as he consistently points out it has been very much a team effort – and the team also collectively deserve every bit of the credit.

As somebody who's believed in the liberatory powers of social networks for decades, I've never been as excited about a project as I am about Blacksky. And I for one am very much looking forward to what comes next – and looking for ways to help!

Speaking of which, at the risk of repeating myself ...

Blacksky primarily relies on crowdfunding.
Please join me in supporting them!

Appendix: links on Bluesky and decentralization that are worth reading even though they don't mention Blacksky

If you're interested in decentralized social networks, there's a lot to learn from various perspectives on Bluesky and decentralization. Alexia's Bluesky, and what Bluesky is not is a good introduction to Bluesky's approach and how it contrasts with ActivityPub. Laurens Hof's A conceptual model of ATProto and ActivityPub and Bluesky, decentralisation, and the distribution of power are two other good fairly-recent overviews.

Christine Lemmer-Webber's How decentralized is Bluesky really? and Bluesky engineer Bryan Newbold's Reply on Bluesky and Decentralization, and Lemmer-Webber's Re: Re: Bluesky and Decentralization are deeper dives on some of the key issues. Both agree that Bluesky's focus on "credible exit" is worthwhile, and highlight the difference between AT Proto's "shared heap" approach and the message-passing architecture of ActivityPub, XMPP, and email. However, they disagree on a lot of other topics, starting with the definition of "decentralization."

Newbold uses Mark Nottingham's definitinn in RFC 9518: Centralization, Decentralization, and Internet Standards (which in turn is based on Paul Baran's 1964 definition in "On Distributed Communications: I. Introduction to Distributed Communication Networks)

[Decentralization is when] "complete reliance upon a single point is not always required"

Lemmer-Webber views this definition as too weak ("decentralization washing"), and suggests that contemporary nomenclature positions "centralized" and "decentralized" as polar ends of a spectrum (in contrast with Baran's terminology, which positioned "centralized" and "distributed" at the ends). Accordingly, Lemmer-Webber's definition is

Decentralization is the result of a system that diffuses power throughout its structure, so that no node holds particular power at the center.

Lemmer-Webber and Newbold also discuss the natural centralizing tendency of search engines in big-world public networks. Even if alternative whole-network Relays do emerge, will the costs and liability of running one be so high that only a few large companies can afford to do so? As the email and XMPP examples highlight, this kind of near-total capture by a few entities is a risk of any decentralized protocol (see for example Embrace, Extend, and Exploit: Meta’s plan for ActivityPub, Mastodon and the Fediverse), so now's certainly a good time to be discussing how this applies to AT!

And those articles are only the tip of the iceberg.

Other perspectives arguing that Bluesky isn't really decentralized include

• Michał "rysiek" Woźniak's April 2023 BlueSky is cosplaying decentralization describes Bluesky as “ostensibly decentralized.” This was written in April 2023, before Blacksky existed, so gets a pass on the erasure front ... and even though s lot has changed since it was written, it's still worth reading!
• jonny (good kind) talks about the "mirage of decentralization in atproto", noting that "i am not concerned with decentralization for decentralization's sake, as a technological fetish, but the implications on the social, political, and economic structure of the system - specifically its capacity to be turned into an extractive chokepoint by those that control the center (the relay)," and has written that AT's relay system is "decentralized in the same sense as google alerts is decentralized"
• Possibly a Dog, in a thread that led to discussion on Hacker News, says "It's not decentralized. #BlueSky is a centralized corporate app, running a theoretically-decentralized network protocol that currently has only one (1) active node on the network: BlueSky."
• Oblomov's A credible threat to (and from) commercial social network silos/2 suggests that "the purported decentralization theoretically made possible by ATproto is largely performative"
• EFF's What You Should Know When Joining Bluesky states "the current Bluesky network is not decentralized," and suggests that even once "credible exit" is possible it still "falls short of the distributed power and decision making of decentralized networks."
• Mike Sass' Cloudy with a chance of not enshittifying says "I’ll say that Bluesky is in no meaningful way decentralized at the moment.... But can Bluesky be decentralized? This is up for debate it seems."

Then again, others argue that Bluesky and AT are decentralized.

• The Related Work sections of Bluesky and the AT Protocol: Usable Decentralized Social Media (and Jay Graber's the earlier 2021 Ecosystem Overview) sites AT and Bluesky in the context of other decentralized social networking technologies.
• In Decentralization or Noncentralization, Bluesky or the Fediverse?, Robert Gehl (author of the upcoming Move Slowly and Build Bridges, a book about the fediverse) argues that "Bluesky has started out centralized and is slowly spinning out parts of itself from the center to the edges," so is decentralized in the sense of de-centering (as opposed to the ActivityPub Fediverse which is non-centralized)
• Kye Fox' Nobody cares about decentralization until they do makes the case that "most people don't care about decentralization now. When they do, more will be happy with the recovery paths available if they choose a platform on the AT protocol."
• In Decentralisation, Michael Exon suggests that "By delegating control over labellers to independent communities, BlueSky has taken the most important step towards decentralisation in a political sense."

And in Hacker News, pxoe suggests it's actually Mastodon that isn't decentralized, a position Chris Hornberger also took in Mastodon isn’t ‘decentralized’ and won’t be the next big thing (2023) and I've heard similar points from more than one peer-to-peer network advocate in the past.

Power in the ActivityPub Fediverse has historically been somewhat centralized as well; Mastodon gGmbH (which controls the code base adn the mobile apps as running mastodon.social, historically by far the largest instance in the Fediverse) and the W3C SWICG (which controls the spec) together had enough power that they brought innovation to a crawl from 2018-2022 are are still major barriers to progress. As Hrefna points out, noting that users have very few remediations if the admin of mastodon.social goes to war with them,

"[W]hile in _theory_ ActivityPub is decentralized, in _practice_ the predominant system for this is _not_ decentralized as far as your median user is concerned."

Using Lemmer-Webber's definition, it seems to me that they both have "particular power" at the center of the network that isn't diffused. So does that mean that the ActivityPub Fediverse isn't decentralized? I'd still say that it is, although not completely ... but your mileage may vary.

So it's all messy and confusing. Welcome to the fediverses.

But as interesting as all these articles are, what's even more interesting to me is that none of them talk about Blacksky. Funny how that works!

Update log

Ongoing: minor fixes (typos, wording changes) and additional links

December 2: originally published

December 15-16: updated to reflect Lemmer-Webber's Re: Re: Bluesky and Decentralization

March 3, 2025: add update from TechPolicy podcast

July 8: add updates and links to Blacksky's Relay and AppView, and the Politics of Protocols draft. Also worth mentioning (although not yet sure where to put it): after a successful crowdfunding campaign, Blacksky is beginning development on an app as well.

August 28: start adding new epilogue-in-progress

September 11: replace most of the epilogue-in-progress with a link to This is what solidarity looks like