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Hey folks! We're excited to share a preview of a new API coming in #Fedify 1.6 that should make structuring larger federated apps much cleaner: FederationBuilder.

As your Fedify applications grow, you might encounter circular dependency issues when registering dispatchers and listeners across multiple files. The new FederationBuilder pattern helps solve this by separating the configuration phase from instantiation.

Instead of this:

// federation.ts
import { createFederation } from "@fedify/fedify";

export const federation = createFederation<AppContext>({
  kv: new DbKvStore(), 
  queue: new RedisMessageQueue(),
  // Other options...
});

// Now we need to import this federation instance in other files
// to register dispatchers and listeners...

You can now do this:

// builder.ts
import { createFederationBuilder } from "@fedify/fedify";

export const builder = createFederationBuilder<AppContext>();

// other files can import and configure this builder...

// actors.ts
import { builder } from "./builder.ts";
import { Person } from "@fedify/fedify";

builder.setActorDispatcher("/users/{handle}", async (ctx, handle) => {
  // Actor implementation
});

// inbox.ts
import { builder } from "./builder.ts";
import { Follow } from "@fedify/fedify";

builder.setInboxListeners("/users/{handle}/inbox", "/inbox")
  .on(Follow, async (ctx, follow) => {
    // Follow handling
  });

// main.ts — Only create the Federation instance at startup
import { builder } from "./builder.ts";

// Build the Federation object with actual dependencies
export const federation = await builder.build({
  kv: new DbKvStore(),
  queue: new RedisMessageQueue(),
  // Other options...
});

This pattern helps avoid circular dependencies and makes your code more modular. Each part of your app can configure the builder without needing the actual Federation instance.

The full documentation will be available when 1.6 is released, but we wanted to share this early with our community. Looking forward to your feedback when it lands!

Want to try it right now? You can install the development version from JSR or npm:

# Deno
deno add jsr:@fedify/fedify@1.6.0-dev.777+1206cb01

# Node.js
npm add @fedify/fedify@1.6.0-dev.777

# Bun
bun add @fedify/fedify@1.6.0-dev.777

We're excited to announce the release of Fedify 1.5.0! This version brings several significant improvements to performance, configurability, and developer experience. Let's dive into what's new:

Two-Stage Fan-out Architecture for Efficient Activity Delivery

#Fedify now implements a smart fan-out mechanism for delivering activities to large audiences. This change is particularly valuable for accounts with many followers. When sending activities to many recipients, Fedify now creates a single consolidated message containing the activity payload and recipient list, which a background worker then processes to re-enqueue individual delivery tasks.

This architectural improvement delivers several benefits: Context.sendActivity() returns almost instantly even with thousands of recipients, memory consumption is dramatically reduced by avoiding payload duplication, UI responsiveness improves since web requests complete quickly, and the system maintains reliability with independent retry logic for each delivery.

For specific requirements, we've added a new fanout option with three settings:

// Configuring fan-out behavior
await ctx.sendActivity(
  { identifier: "alice" },
  recipients,
  activity,
  { fanout: "auto" }  // Default: automatic based on recipient count
  // Other options: "skip" (never use fan-out) or "force" (always use fan-out)
);

Canonical Origin Support for Multi-Domain Setups

You can now explicitly configure a canonical origin for your server, which is especially useful for multi-domain setups. This feature allows you to set different domains for WebFinger handles and #ActivityPub URIs, configured through the new origin option in createFederation(). This enhancement prevents unexpected URL construction when requests bypass proxies and improves security by ensuring consistent domain usage.

const federation = createFederation({
  // Use example.com for handles but ap.example.com for ActivityPub URIs
  origin: {
    handleHost: "example.com",
    webOrigin: "https://ap.example.com",
  },
  // Other options...
});

Optional Followers Collection Synchronization

Followers collection synchronization (FEP-8fcf) is now opt-in rather than automatic. This feature must now be explicitly enabled through the syncCollection option, giving developers more control over when to include followers collection digests. This change improves network efficiency by reducing unnecessary synchronization traffic.

await ctx.sendActivity(
  { identifier: sender },
  "followers",
  activity,
  { 
    preferSharedInbox: true,
    syncCollection: true,  // Explicitly enable collection synchronization
  }
);

Enhanced Key Format Compatibility

Key format support has been expanded for better interoperability. Fedify now accepts PEM-PKCS#1 format in addition to PEM-SPKI for RSA public keys. We've added importPkcs1() and importPem() functions for additional flexibility, which improves compatibility with a wider range of ActivityPub implementations.

Improved Key Selection Logic

The key selection process is now more intelligent. The fetchKey() function can now select the public key of an actor if keyId has no fragment and the actor has only one public key. This enhancement simplifies key handling in common scenarios and provides better compatibility with implementations that don't specify fragment identifiers.

New Authorization Options

Authorization handling has been enhanced with new options for the RequestContext.getSignedKey() and getSignedKeyOwner() methods. This provides more flexible control over authentication and authorization flows. We've deprecated older parameter-based approaches in favor of the more flexible method-based approach.

Efficient Bulk Message Queueing

Message queue performance is improved with bulk operations. We've added an optional enqueueMany() method to the MessageQueue interface, enabling efficient queueing of multiple messages in a single operation. This reduces overhead when processing batches of activities. All our message queue implementations have been updated to support this new operation:

• @fedify/redis 0.4.0
• @fedify/postgres 0.3.0
• @fedify/amqp 0.2.0

If you're using any of these packages, make sure to update them alongside Fedify to take advantage of the more efficient bulk message queueing.

CLI Improvements

The Fedify command-line tools have been enhanced with an improved web interface for the fedify inbox command. We've added the Fedify logo with the cute dinosaur at the top of the page and made it easier to copy the fediverse handle of the ephemeral actor. We've also fixed issues with the web interface when installed via deno install from JSR.

Additional Improvements and Bug Fixes

• Updated dependencies, including @js-temporal/polyfill to 0.5.0 for Node.js and Bun
• Fixed bundler errors with uri-template-router on Rollup
• Improved error handling and logging for document loader when KV store operations fail
• Added more log messages using the LogTape library
• Internalized the multibase package for better maintenance and compatibility

For the complete list of changes, please refer to the changelog.

To update to Fedify 1.5.0, run:

# For Deno
deno add jsr:@fedify/fedify@1.5.0

# For npm
npm  add     @fedify/fedify@1.5.0

# For Bun
bun  add     @fedify/fedify@1.5.0

Thank you to all contributors who helped make this release possible!