What is Bluesky? Why tens of millions of people are heading for a ‘decentralised’ social media platform

After Elon Musk bought Twitter (now rebranded X) in 2022, disaffected users began to seek alternatives. Alongside Meta’s Threads and the open source project Mastodon, Bluesky was one of several contenders.

Threads benefited from Meta’s existing user base but has failed to capture the popular imagination. Mastodon has proven complicated and difficult to grasp for most ordinary users and so use remains fragmented. Bluesky seemed promising but was in invite-only mode at the time and growth was muted.

But in recent weeks, the migration to Bluesky from X seems to have reached a tipping point, as large parts of the user community finally got fed up with X’s toxic culture and management. Following the recent US presidential election, in which Musk appeared to manipulate X’s algorithms to increase his own influence, these users found Bluesky’s doors wide open.

Since then, the user base has grown to more than 20 million users, a number that continues to climb. As others have noted, at least for the moment it feels a bit like early Twitter – a sandpit to explore new tools, a playful connection to the broader internet, and a relatively safe place to share personal thoughts and experiences, or to connect with friends and colleagues.

How is Bluesky different from X?

Bluesky looks very similar to X. Its azure butterfly icon bears obvious resemblances to Twitter’s blue bird, which Musk replaced with a stark white-on-black X.

Bluesky uses hashtags and users address one another using the @ symbol. Replies, quotes and reposts all work much as they do on X. This comforting resemblance is likely one explanation for the remarkable popularity of Bluesky in comparison to other decentralised platforms such as Mastodon.

Bluesky distinguishes itself from X through a rich set of features through which users can control their experience and shape the culture of the platform as a whole.

You can build multiple custom feeds based on your own interests and relationships then publicly share these feeds with others. This is a powerful mechanism to avoid the one-way “push” of algorithmic feeds and represents a more democratic approach to content curation.

Bluesky offers the ability to create custom “starter packs” – curated lists of suggested accounts related to topics, interests or locations. Starter packs can be shared publicly to help new users find people to follow. This is a novel feature that feels friendly and welcoming, and again doesn’t really rely on a top-down algorithm.

Bluesky’s settings menu also includes powerful content moderation tools that users can control. For example, you can create custom keyword lists to mute some types of content, and control who can interact with you.

This means if you don’t want to listen to certain political views, you don’t have to. It also means you can have a pleasant and sociable time without being subject to hate speech, bullying and harassment.

Critics argue these kinds of user controls will lead to “echo chambers” so the overall public sphere (or public square) is no longer a place for an exchange of differing views. But as I have previously argued, a public square owned by a billionaire that is full of shouting bullies does nothing to enable equal participation either.

How decentralised is Bluesky?

Bluesky began life in 2019 as an experimental project within Twitter, led by co-founder and former CEO Jack Dorsey.

The idea was to implement for social media a decentralised protocol – a system that prevents complete control by a single organisation and enables developers or users to build improvements. This would also enable Twitter to connect, or “federate”, with other decentralised platforms and services such as Mastodon.

Rather than being adopted by Twitter, Bluesky eventually became a standalone project and then corporation (Dorsey is no longer involved). There are debates as to how truly decentralised and interoperable it is: Bluesky uses its own AT Protocol (ATP), rather than the ActivityPub protocol commonly used throughout the broader “fedisphere” of decentralised social media. Critics argue this choice could limit Bluesky’s reach and hinder interaction across platforms. For example, a “bridge” is needed to connect Bluesky and Mastodon accounts.

Still, like other federated platforms, it is possible for users to host their accounts on their own servers or nodes. At least in principle, the platform, content, users and their relationships could continue to exist even if the Bluesky company were to disappear, or “exit”, in technical terms.

This is a big shift away from one private company owning all the servers, controlling all the algorithms and making all the rules, and so the next phase of Bluesky’s development will depend substantially on the actions of its users.

Blue skies ahead?

As Bluesky rapidly grows larger, familiar questions are beginning to emerge.

How will a small team relying primarily on community-led content moderation handle adversarial swarms of political bots or child sexual abuse material? Will it accept responsibility for the spread of harmful misinformation or manipulation of political opinion? The company is already investing more in trust and safety but more will be needed if Bluesky’s popularity continues to grow.

The organisation’s funding largely comes from libertarian-leaning cryptocurrency investors. The company has been clear advertising will not be part of the mix and has mentioned introducing paid services as an alternative revenue source. It is unclear whether such strategies will be enough to support a far larger operation, and whether the investors will remain neutral as difficult decisions on platform governance have to be made.

Growth may also bring more government interest. If Bluesky reaches more than 45 million EU users per month, it may be categorised as a “very large online platform”, and will face increased scrutiny.

Questions also remain about whether the “Xodus” to Bluesky will stick. A growth in new sign-ups is one thing, but a vibrant community that is actively posting, sharing and commenting is another matter entirely.

It is doubtful we will ever see a full replacement for Twitter in its heyday, and maybe that’s OK. As long as there is some interoperability between platforms and a healthy exchange of ideas, it may be better if we never again put all our little blue eggs in one basket.

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