A Guide to Getting Started with the AT Protocol

By Tierney Cyren | Originally published August 25, 2026

I have spent a significant amount of time trying to persuade my software engineering peers to dive into the AT Protocol. Usually, this involves sending a barrage of individual links. To streamline this process, I've compiled this comprehensive resource list so I can share a single URL instead of a dozen.

Note on Updates: I will keep this list current. To track revisions, I'll insert my most-used emoji in parentheses at the top. Since there are no established rules for this, we start now: (💕👀).

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🧠 Understanding the AT Protocol

To truly grasp "atmospheric thinking," there are a few foundational pieces of writing I return to constantly.

• "A Social Filesystem" by Dan Abramov: This is essential reading for any human who has ever used a computer and wants to understand the AT Protocol.
• "There Are No Instances in atproto" by Dan Abramov: This is particularly helpful if you have experience with the Fediverse.
  • Personal Context: I started with Tent (which was separate from the Fediverse) just as Mastodon and Diaspora* were gaining traction.
  • I am not anti-fediverse (Hacker News, please believe me). However, I believe this post is the best way to "de-fediverse" your mental model so you can approach AT Protocol with a fresh perspective.
• "Let's Talk Money" by Joe Basser: An exhaustive exploration of currency within the AT Protocol, culminating in ATM (Atmosphere Money), which Joe helped develop. I believe ATM is a brilliant, unique approach and I'm rooting for its success.

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🌌 The Concept of "Spaces"

Added in the first edit. Spaces are critical because they dictate how the AT Protocol surfaces data, unlocking entirely new application categories.

Whether you're dreaming of an AT Protocol-based Dropbox (please be mindful of your PDS load!) or adding a "Close Friends" feature to a social app (looking at you, Bluesky), Spaces make these possibilities real.

Key Reading on Spaces:

1. "The Atproto Spaces Alpha is Live" by Daniel Holmgren: The primary entry point for understanding Spaces as a mechanism for private data within the Atmosphere. Many developers were waiting for this specific piece before they started building.
2. "Reintroducing Spaces" by Daniel Holmgren: A follow-up post to the alpha launch. Reading this was a revelation for me; it felt as though Daniel took every hope I had for Spaces and published them on Leaflet.

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📖 Lexicons

The Standard.site lexicon for community-owned long-form content is, in my view, the most vital indicator of the ecosystem's health (outside of Bluesky's general success). It proves that the community can coalesce around a standard data format independently of the Bluesky PBC.

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💾 Data Architecture

At its core, the AT Protocol is centered on data ownership. While the reality is more complex, you can get $\approx 80\%$ of the way there with this conceptual formula:

$\text{Lexicons (Structure)} \rightarrow \text{Records (Stored on PDS)} \rightarrow \text{Protocol (Movement)}$

Data Flow Visualization

Technical Resources for Data

• HappyView: AppViews are often cited as the most difficult hurdle in AT Protocol development. HappyView makes this process trivial.
• bluesky-social/pds: The official reference implementation. Despite some criticisms, it remains the gold standard for reference.
• Tranquil PDS: Frequently recommended to me as the premier deployable PDS option.

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🛠️ Utilities

Here is a collection of tools I've either used personally or am eager to integrate into my workflow.

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🚀 Built with AT Protocol

To demonstrate that this isn't just about creating "Twitter clones," look at these diverse implementations:

• Data Visualization: A project that binds and visualizes protocol data (though its browser-only nature may limit consumer adoption).
• PDS Music: A SoundCloud-like experience where the audio files are hosted directly on the users' PDSes.
• Marque: A nifty interface for users who want to register and link their own domains to their accounts.

🏁 Getting Started Checklist

• Read "A Social Filesystem"
• Explore atproto.at
• Set up a PDS (Reference or Tranquil)
• Experiment with a Lexicon

// Example of a conceptual AT Protocol record
{
  "type": "com.example.greeting",
  "value": {
    "text": "Hello, Atmosphere!",
    "timestamp": "2026-08-25T12:00:00Z"
  }
}

Final thought: If you're the one who built the domain tool, I might still be hesitant, but I'm open to it!