* :heavy_check_mark: [**ActivityPhp**](https://github.com/landrok/activitypub) ([site](https://landrok.github.io/activitypub), [Fedi account](https://cybre.space/@landrok)): A PHP implementation of ActivityPub protocol based upon the ActivityStreams 2.0 data format. `MIT, PHP`
* :heavy_check_mark: [**ActivityPub-PHP**](https://github.com/pterotype-project/activitypub-php) ([Fedi account](https://mastodon.technology/@jdormit)): A PHP implementation of the ActivityPub protocol (used in Pterotype plugin). `MIT, PHP`
* :heavy_check_mark: [**activityPub4j**](https://github.com/msummers/activityPub4j): W3C ActivityPub and ActivityStreams implementation in Java using Spring Boot. `Apache-2.0, Java`
* :heavy_check_mark: [**ActivityStreams**](https://github.com/OpenSocial/activitystreams): Full ActivityStreams 1.0 and 2.0 reference implementation in Java. `Apache-2.0, Java`
* :black_nib: [**ActivityServe**](https://github.com/writeas/activityserve): A very light ActivityPub library in Go (used to power [pherephone](https://github.com/writeas/pherephone)) `MIT, Go`
* :heavy_check_mark: [**astreams**](https://github.com/MatejLach/astreams) ([Fedi account](https://social.matej-lach.me/@MatejLach)): A hand-crafted implementation of the Activity Streams 2.0 specification in Go, especially suitable for projects implementing ActivityPub. `AGPL-3.0, Go`
* :heavy_check_mark: [**atoot**](https://github.com/popura-network/atoot): Library providing an easy way to create Mastodon API applications `MIT, Python`
* :black_nib: [**Clovis**](https://github.com/WellFactored/clovis): [ARCHIVED] Implementation of ActivityPub in Scala. (Hobby project included here for reference only.) `AGPL-3.0, Scala`
* :heavy_check_mark: [**CommonsPub**](https://gitlab.com/CommonsPub) ([site](http://commonspub.org)): Building blocks for creating multifunctional federated networks with ActivityPub. `AGPL-3.0, Elixir`
* :heavy_check_mark: [**corpus-activity-streams**](https://github.com/ryanatkn/corpus-activity-streams): Activity Streams 2.0 vocabulary data and alternative docs. `Unlicense license, Typescript`
* :black_nib: [**dda-masto-embed**](https://github.com/DomainDrivenArchitecture/dda-masto-embed) ([Fedi account](https://social.meissa-gmbh.de/@team)): Embeds mastodon timline into a html page. Uses JS, no intermediate server required. `Apache-2.0, ClojureScript`
* :heavy_check_mark: [**Express ActivityPub**](https://github.com/dariusk/express-activitypub): A very simple reference implementation of an ActivityPub server using Express.js. `MIT, Javascript`
* :heavy_check_mark: [**Federation**](https://git.feneas.org/jaywink/federation): Library to abstract social web federation protocols like ActivityPub, Diaspora and Matrix (see [docs](https://federation.readthedocs.io)) `BSD-3-clause, Python`
* :heavy_check_mark: [**Golang ActivityPub**](https://github.com/go-ap) ([Fedi account](https://metalhead.club/@mariusor)): Libraries for using ActivityPub in the Go language. `MIT, Go`
* :heavy_check_mark: [**go-fed activity**](https://github.com/go-fed/activity) ([site](https://go-fed.org), [Fedi account](https://mastodon.technology/@cj)): Full ActivityStreams & ActivityPub implementation in Golang. Extensions can be easily added by design-time code generation from JSON-LD schema's (also supports [ForgeFed](https://forgefed.peers.community) this way, by default). `BSD-3-clause, Go`
* :heavy_check_mark: [**go-fed apcore**](https://github.com/go-fed/apcore) ([site](https://go-fed.org), [Fedi account](https://mastodon.technology/@cj)): A powerful single server ActivityPub framework for performant Fediverse applications. `AGPL-3.0, Go`
* :heavy_check_mark: [**http-signature**](https://github.com/mtti/http-signature): Implementation of the HTTP Signature scheme as used in ActivityPub. `Apache-2.0, Typescript`
* :heavy_check_mark: [**Little Boxes**](https://little-boxes.readthedocs.io): Tiny ActivityPub framework, both database and server agnostic `ISC, Python`
* :heavy_check_mark: [**Little Library**](https://github.com/Alamantus/little-library): A digital give-a-book, take-a-book library for ebooks `AGPL-3.0, Javascript`
* :heavy_check_mark: [**Pubstrate**](https://gitlab.com/dustyweb/pubstrate): ActivityStreams and ActivityPub library implementation for GNU Guile. Includes a full ActivityStreams library and most of an ActivityPub implementation. `GPL-3.0, Guile`
* :heavy_check_mark: [**ActivityPub for Drupal**](https://github.com/swentel/activitypub) ([Lead dev](https://realize.be/user/1)): ActivityPub integration for Drupal 8 (see also [lite version](https://www.drupal.org/project/activitypub/) at Drupal) `GPL-2.0, PHP`
* :heavy_check_mark: [**Hugo-ActivityStreams**](https://git.jlel.se/jlelse/hugo-activitystreams): A Hugo module for use in Hugo, to generate ActivityStreams representations of posts. ([mirror](https://codeberg.org/jlelse/hugo-activitystreams)) `MIT, Go`
* :heavy_check_mark: [**Pterotype**](https://github.com/pterotype-project/pterotype): WordPress plugin. Pterotype connects your blog to the Fediverse by giving it an ActivityPub feed `MIT, PHP`
* :heavy_check_mark: [**XWiki Extension for ActivityPub**](https://github.com/xwiki-contrib/application-activitypub) ([site](https://extensions.xwiki.org/xwiki/bin/view/Extension/ActivityPub%20Application/), [Fedi account](https://social.weho.st/@XWiki)): An implementation of the ActivityPub protocol for XWiki (see [forum discussion](https://forum.xwiki.org/t/new-application-activitypub/6186)). `LGPL-2.1, Java`
* :heavy_check_mark: [**Activity Relay**](https://git.pleroma.social/pleroma/relay): A generic LitePub relay (works with all LitePub consumers and Mastodon). `AGPL-3.0, Python`
* :heavy_check_mark: [**Social relay**](https://git.feneas.org/jaywink/social-relay): Public post relay for the diaspora* federated social network protocol. `AGPL-3.0, Python`
* :heavy_check_mark: [**BridgyFed**](https://github.com/snarfed/bridgy-fed) ([site](https://fed.brid.gy)): Bridges the IndieWeb to federated social networks: ActivityPub, OStatus, etc. `Public Domain, Python`
* :heavy_check_mark: [**Fediverse-Action**](https://github.com/rzr/fediverse-action): Github Action that posts to Fediverse when code is changed. `ISC License, Javascript`
* :heavy_check_mark: [**feed2toot**](https://gitlab.com/chaica/feed2toot): Parses RSS feeds, identifies new posts and posts them on the Mastodon social network ([using the Mastodon API]((https://gitlab.com/chaica/feed2toot/issues/35#note_289027030))). `MIT, Python`
* :heavy_check_mark: [**gemifedi**](https://git.sr.ht/~boringcactus/gemifedi): A Gemini frontend to the fediverse (specifically, Mastodon and Pleroma instances). `AGPL-3.0, Rust`
* :heavy_check_mark: [**Instagram2Fedi**](https://github.com/Horhik/Instagram2Fedi): Script for crossposting from Instagram to Mastodon or Pixelfed. `GPL-3.0, Python`
* :heavy_check_mark: [**ligh7hau5**](https://github.com/vulet/ligh7hau5): A Matrix to Fediverse / ActivityPub client / bridge. Also, some media proxying. `GPL-3.0, Javascript`
* :heavy_check_mark: [**mastodon-twitter-poster**](https://github.com/renatolond/mastodon-twitter-poster) ([site](https://crossposter.masto.donte.com.br/), [Fedi account](https://masto.donte.com.br/@crossposter)): Crossposter to post statuses between Mastodon and Twitter. `AGPL-3.0, Ruby`
* :heavy_check_mark: [**MXToot**](https://github.com/ma1uta/mxtoot) ([Fedi account](https://mastodon.social/@ma1uta)): A Matrix <--> Mastodon bot written in Java. `Apache-2.0, Java`
* :heavy_check_mark: **[Nautilus](https://github.com/aaronpk/Nautilus)**: A standalone service to deliver posts from your own website to ActivityPub followers. `Apache-2.0, PHP`
* :heavy_check_mark: **[PeerTube (on Matrix) Search](https://github.com/vranki/hemppa#peertube-search)**: Search PeerTube via Matrix, using Sepia Search API to search on all participating public PeerTube instances. You can also select any single instance. It's implemented as a module for Hemppa the bot. `GPL-3.0, Python`
* :heavy_check_mark: [**rss-bot**](https://alexschroeder.ch/cgit/rss-bot/) ([Fedi account](https://octodon.social/@kensanata)): Post updates from an RSS feed to Mastodon. `GPL-3.0, Python`
* :heavy_check_mark: [**RSS-to-ActivityPub Converter**](https://github.com/dariusk/rss-to-activitypub): Convert any RSS feed to an ActivityPub actor that can be followed by users on ActivityPub-compliant social networks like Mastodon. `MIT, Javascript`
* :heavy_check_mark: [**Twitter Hamachpil**](https://gitlab.com/hamachpil/twitter_hamachpil) ([Fedi account](https://emacsen.net/@emacsen)): Bot to grab tweets from Twitter and post them to respective accounts on a Mastodon instance. `Apache-2.0, Python`
* :heavy_check_mark: **[YouTube2PeerTube](https://github.com/mister-monster/YouTube2PeerTube)**: A bot that mirrors YouTube channels to PeerTube channels as videos are released in a YouTube channel. `AGPL-3.0, Python`
* :black_nib: [**ActivityPubSchema**](https://github.com/redaktor/ActivityPubSchema): JSON Schema definition of the ActivityStreams and ActivityPub specifications. `MIT, Javascript`
* :heavy_check_mark: [**bridge**](https://source.joinmastodon.org/mastodon/bridge): A simple web app that helps you find your Twitter friends on the federated Mastodon network. It is also an example of how the Mastodon API can be used and the federated OAuth authorization flow. `AGPL-3.0, Ruby`
* :heavy_check_mark: [**FediHealth**](https://git.feneas.org/buttle/fedihealth): Software to help you define federation policies for your node. `AGPL-3.0, Python`
* :heavy_check_mark: [**Fediverse Stats**](https://gitlab.com/spla/fediverse) ([Fedi account](https://mastodont.cat/@fediverse)): Collects maximum number of alive fediverse's servers and then query their API to obtain their registered users. `GPL-3.0, Python`
* :heavy_check_mark: [**forget**](https://github.com/codl/forget) ([site](https://forget.codl.fr/), [Fedi account](https://chitter.xyz/@codl)): Continuous post deletion for Mastodon and Twitter (if you happen to use that). `ISC License, Python`
* :black_nib: [**mastodon-backup**](https://github.com/kensanata/mastodon-backup) ([Fedi account](https://octodon.social/@kensanata)): Archive your statuses, favorites and media using the Mastodon API. `GPL-3.0, Python`
* :heavy_check_mark: **[Mastotool](https://github.com/muesli/mastotool)**: A collection of tools to work with your Mastodon account; displays account statistics and lets you search your toots. `MIT, Go`
* :heavy_check_mark: [**Pherephone**](https://github.com/writeas/pherephone): An ActivityPub server that reblogs all the statuses of certain actors. You set it up to follow a few accounts and it announces everything they post. `AGPL-3.0, Go`
* :heavy_check_mark: [**tags-pub**](https://gitlab.com/evanp/tags-pub): Provides hashtag objects on the ActivityPub network. `Apache-2.0, Javascript`
* :heavy_check_mark: [**yt2pt**](https://github.com/buoyantair/yt2pt): A simple set of scripts to quickly import your youtube channel to Peertube. `MIT, Javascript`
* :heavy_check_mark: [**activitypub-mock**](https://gitlab.com/evanp/activitypub-mock): A mock ActivityPub server to use in testing code `Apache-2.0, Javascript`
* :black_nib: [**dfk-ap**](https://glitch.com/edit/#!/dfk-ap?path=README.md%3A1%3A0) ([site](https://tinysubversions.com/notes/activitypub-tool/)): A small ActivityPub debugging server on Glitch `MIT, Javascript`
* :heavy_check_mark: [**FediDB**](https://fedidb.org/about): A suite of tools for AP devs to help make it easier to test and validate your implementation with existing implementations like Mastodon, PeerTube, Pixelfed and Pleroma `-, -`
* :black_nib: [**Sepia Search**](https://framagit.org/framasoft/peertube/search-index/) ([site](https://sepiasearch.org/)): A search engine of PeerTube videos and channels Developed by Framasoft `AGPL-3.0, Typescript`
* :heavy_check_mark: [**Share Buttons**](https://git.fsfe.org/FSFE/share-buttons): Share buttons that support dynamic input of Fediverse URLs and require no Javascript. `AGPL-3,0, PHP`
* :heavy_check_mark: [**Share Freedom**](https://gitlab.com/mugcake/share-freedom-extension): Firefox toolbar extension to share the current browser tab to the Fediverse `GPL-3.0, Javascript`
* :black_nib: [**Mastodon Simplified Federation**](https://github.com/rugk/mastodon-simplified-federation): Simplifies following and interacting with remote users on other Mastodon instances. `ISC, Javascript`
* :heavy_check_mark: [**ForgeFed**](https://notabug.org/peers/forgefed), formerly GitPub ([site](https://forgefed.peers.community), [Fedi account](https://floss.social/@forgefed)): A set of extensions to ActivityPub for federation between code forges (i.e. git hosting sites like GitLab, Gogs, Gitea, etc. Reference implementation is [Vervis](https://dev.angeley.es/s/fr33domlover/p/vervis)). `CC0-1.0`
* :heavy_check_mark: [**LitePub**](https://github.com/litepub/litepub) ([Fedi account](https://pleroma.site/users/kaniini)): A set of extensions to AP, being developed by devs from Pleroma and Mastodon (status: for the most part litepub group folded back into SocialCG, see: [issue](https://github.com/litepub/litepub/issues/6))
* :heavy_check_mark: [**NodeInfo2**](https://git.feneas.org/jaywink/nodeinfo2): An effort to create a standardized way of exposing metadata about a server. Helps expose ownership and organization details, usage statistics and protocol capabilities. `CC0-1.0`
* :black_nib: [**Podcasting**](https://github.com/Podcastindex-org/activitypub-spec-work): Workspace for defining ActivityPub and ActivityStream extensions for Podcasting with the intention to define a W3C Recommendation for them.
* :heavy_check_mark: [**SciFed**](https://synalp.frama.io/olki/scifed/) (Fedi accounts: [@rigelk](https://olki-social.loria.fr/@rigelk), [@cerisara](https://mastodon.etalab.gouv.fr/@cerisara)): A specification standard (Draft) for federation of scientific activities and content using ActivityPub, developed as part of the [OLKi](https://olki.loria.fr/) project.
* :black_nib: [**The did:orb Method**](https://trustbloc.github.io/did-method-orb/) ([github](https://github.com/trustbloc/did-method-orb)): A DID Method for a fediverse of interconnected nodes and witnesses.
* :black_nib: [**Content-addressible RDF**](https://openengiadina.net/papers/content-addressable-rdf.html): A scheme based on RDF allowing for data to be referred to by an identifier determined by the data itself (written by @pukkamustard of [openEngiadina](https://openengiadina.net), specification now part of [DREAM](https://dream.public.cat/pub/dream-data-spec))
* :black_nib: [**Encoding for Robust Immutable Storage** (ERIS)](https://inqlab.net/projects/eris/): ERIS is an encoding of arbitrary content into a set of uniformly sized, encrypted and content-addressed blocks as well as a short identifier (a URN) (written by @pukkamustard of [openEngiadina](https://openengiadina.net), specification now part of [DREAM](https://dream.public.cat/pub/dream-data-spec)).
* :black_nib: [**Distributed Mutable Containers** (DMC)](https://inqlab.net/projects/dmc/): Distributed data structures that can hold references to content while allowing replicas of the data structures to diverge and merge without conflict (developed by [DREAM](https://dream.public.cat/pub/dream-data-spec))
