Misskey

What is Misskey?

Misskey is an open source, self-hosted microblogging server that runs on the fediverse via the ActivityPub protocol. It lets you run your own social network that federates with other servers — Mastodon, Pixelfed, and others — while giving you full control over the software, the rules, and the data. Its signature feature is emoji reactions: instead of a single like, you react to posts with any Unicode or custom emoji.

What is Misskey best for?

Misskey suits communities and individuals who want a playful, highly customizable microblogging server rather than the more austere feel of stock Mastodon. It’s a strong fit for smaller instances, hobbyist and creative communities, and anyone who wants emoji reactions, animated text, and a themeable UI. Because it federates, your users still reach the wider fediverse.

What can Misskey do?

• Custom emoji reactions — react to any post with Unicode or instance-hosted custom emoji instead of a single like, the core way people interact on Misskey.
• Federation over ActivityPub — connect with users on Mastodon, Pixelfed, and other fediverse servers.
• MFM (Misskey Flavored Markdown) — inline text effects like color, sizing, and animation, plus LaTeX, going well beyond Mastodon’s formatting.
• Highly customizable Web UI — rearrange the layout, add widgets, and build custom themes.
• Drive — built-in cloud file storage where you upload files, organize folders, and reuse media across posts.
• Play — a built-in mini-app platform (AiScript) for creating and sharing interactive apps on your instance.
• Antennas and lists — filter the timeline with keyword-based antennas and custom user lists.

Where does Misskey fall short?

Misskey is not compatible with the Mastodon API, so the large ecosystem of Mastodon mobile apps (Tusky, Ivory, and similar) won’t work with it — you’re limited to the web UI and the smaller set of Misskey-specific clients.

Its rich extras — MFM animations, custom emoji, Play apps — are largely degraded or invisible on other fediverse servers. A follower on Mastodon sees a plainer version of your post, so the experience is best when both sides run Misskey.

The upstream project is Japanese-first, so English documentation and community support lag the original, and a few third-party forks (such as MisskeyIO and Sharkey) have appeared to address gaps, which can make it harder to know which version to run.

Is Misskey free?

Yes — Misskey is completely free and open source under the AGPL-3.0 license. There’s no paid edition and no vendor: you self-host it at no software cost, paying only for the server you run it on. The AGPL means that if you modify Misskey and offer it over a network, you must make your source changes available.

What does Misskey replace?

Misskey is an open source alternative to centralized microblogging networks — chiefly Twitter/X, Threads, and Tumblr. Instead of posting to a platform owned by one company, you run your own federated server (or join someone else’s) and keep control of your feed, your data, and your moderation rules. Within open source, its closest comparison is Mastodon; Misskey trades Mastodon’s app ecosystem for a more customizable, reaction-driven experience.

FAQ

Is Misskey open source? Yes. Misskey is released under the AGPL-3.0 license, and development happens in the open on GitHub. You can read, modify, and self-host the full source.

Can I self-host Misskey for free? Yes. The software is free; you only pay for the server that runs it. Misskey ships with Docker support to simplify setup.

Is Misskey a good Twitter/X alternative? It is if you want a federated network with emoji reactions, animated text, and a customizable UI, and you don’t need Mastodon-compatible mobile apps. For the widest app support instead, Mastodon is the more conservative choice.

What do I need to run Misskey? Misskey runs on Node.js and requires PostgreSQL for storage and Redis for caching. It’s built in TypeScript, uses the pnpm package manager, and provides Docker Compose files for containerized deployment.