fedify

Use when debugging Fedify issues: WebFinger resolution failures, HTTP signature verification errors, activity delivery failures, inbox processing problems, or interoperability issues with Mastodon, Misskey, or other fediverse software.

Use proactively after changes to Fedify-based ActivityPub code to check for best-practice violations, security issues, and interoperability problems. Invoke when reviewing dispatcher implementations, inbox listeners, key pair handling, vocabulary usage, or federation middleware configuration.

Use this skill whenever writing JavaScript or TypeScript code that uses Fedify to build an ActivityPub server, handle federation activities, implement fediverse features, or integrate Fedify with a web framework such as Hono, Express, Next.js, Nuxt, Fastify, Koa, NestJS, Astro, SvelteKit, Fresh, h3, Elysia, or Cloudflare Workers. Covers the `Federation` builder pattern, actor/inbox/outbox/collection dispatchers, inbox listeners, vocabulary objects from `@fedify/vocab`, key pair management, HTTP Signatures, Object Integrity Proofs, the `KvStore` and `MessageQueue` interfaces, database adapter packages, structured logging with LogTape, OpenTelemetry tracing, the `fedify` CLI toolchain, and common mistakes. Also apply when the user mentions ActivityPub, federation, fediverse, WebFinger, NodeInfo, FEPs, or Mastodon interoperability, even if they do not name Fedify explicitly.

Guide the user through implementing an ActivityPub actor with Fedify. Use when the user needs to add or configure an actor dispatcher, set up key pairs, configure aliases, or handle actor-related requests.

Fetch and explain Fedify documentation on a specific topic. Use when the user asks about Fedify API details, configuration options, or how a specific feature works. Fetches up-to-date docs from fedify.dev.

Look up a Fediverse Enhancement Proposal (FEP) and explain how to implement it with Fedify. Use when the user asks about a specific FEP by ID (e.g., FEP-8fcf, FEP-1b12) or wants to implement a fediverse standard in their Fedify application.

Help the user set up Fedify inbox listeners for handling incoming ActivityPub activities. Use when the user needs to handle Follow, Like, Announce, Create, Undo, or other activity types delivered to their inbox.

Help the user migrate Fedify code between versions. Use when the user needs to upgrade their Fedify version, fix breaking-change errors, or update deprecated API usage.