Distribution Without One Central Algorithm

Mastodon is not one giant feed controlled by one central ranking system.

A better first model is connected neighborhoods. A post starts on the author's home server. From there, it can travel through followers, boosts, hashtags, search, server caches, visibility settings, and moderation rules.

That does not mean there are no algorithms anywhere. Servers and clients still sort, filter, cache, search, and display information. The point is narrower: distribution is not owned by one global platform feed.

The home server is the first publishing point

Every account belongs to a home server.

When Alice posts from server-a.example, that server stores the post and makes it available according to the post's visibility. People on the same server may see it through local timelines or search. People on other servers usually learn about it when federation paths connect the servers.

In simple terms:

Alice posts -> Alice's server stores it -> other servers learn about it through relationships and federation

The post lives at an address, but reach depends on which servers know about it and are allowed to show it.

Followers create distribution paths

Following is one of the main rails.

If Ben on server-b.example follows Alice on server-a.example, Ben's server has a reason to receive Alice's public posts. That relationship creates a path between the two neighborhoods.

This is why federated distribution is not global by default. A server does not automatically know every public post on every other server. It knows the posts that reach it through follows, interactions, searches, relays, caches, and other federation paths.

Boosts are redistribution

A boost is not only appreciation. It is also a redistribution action.

In ActivityPub language, a share-like action can be represented with an Announce activity. In Mastodon user language, the result is simpler: someone boosts a post, and that post can appear to a wider audience through the boosting account's relationships.

Alice posts -> Ben boosts -> Ben's audience may now see Alice's post

Boosts matter because they create new paths through the network without requiring one central recommender to decide what everyone should see.

Hashtags and search are discovery rails

Hashtags give software and people a label to search or follow.

A public post with a hashtag can become easier to discover by people looking for that tag. Mastodon documentation also describes followed hashtags as a way for posts to appear in a home feed even when the author is not followed.

But hashtags are not magic global broadcast. Discovery still depends on server knowledge, indexing behavior, visibility, moderation, and client features.

Visibility changes how far a post can travel

Visibility settings shape distribution.

A public post can appear in public timelines and can be boosted. An unlisted post can still be reached but is not shown in the same public timeline surfaces. Follower-only posts are limited to followers and cannot be boosted by others. Mention-only posts are narrower again.

Those settings are not cosmetic. They change the paths a post can use.

Moderation and federation rules shape reach

Federation is not automatic permission to reach everyone.

Servers can apply moderation rules, block other servers, limit content, or refuse certain traffic. Users can block or mute accounts. Communities can have different norms.

This is part of the trade-off. Mastodon gives more local agency than a single central platform, but that also means reach is less predictable.

The useful mental model

Think of a Mastodon post like a notice that starts in one neighborhood.

It can travel through:

1. Followers.
2. Boosts.
3. Hashtags.
4. Search and direct URLs.
5. Server-to-server federation.
6. Visibility settings.
7. Moderation rules.

The network is open enough for posts to cross server boundaries, but not flat enough for every post to be globally visible by default.

Bottom line

Mastodon distribution is relationship-shaped and server-shaped.

That makes it different from a central platform feed. It can give users and communities more agency, but it also asks readers and publishers to understand the rails: followers, boosts, hashtags, visibility, moderation, and federation.

The durable lesson is not only about Mastodon. Any decentralized distribution system has a shape. If you want durable public knowledge, understand the shape before assuming one algorithm will carry the work.

Sources

• Mastodon documentation on network features, posting visibility, hashtags, boosts, and discoverability.
• Mastodon ActivityPub documentation on Create, Announce, Follow, and status federation.
• W3C ActivityPub Recommendation on decentralized social networking, inboxes, outboxes, actors, client-to-server behavior, and server-to-server federation.