Iceshrimp.NET is an open-source, self-hosted Fediverse server built on .NET with Mastodon API support. Explore features, self-hosting and alternatives.
Iceshrimp.NET is a free, open-source, self-hosted server for the ActivityPub Fediverse, built as a from-scratch rewrite of the original Iceshrimp project using C# and the .NET platform instead of JavaScript. It descends from Misskey by way of Calckey/Firefish and the original Iceshrimp fork created in mid-2023.
Unlike most Fediverse servers, Iceshrimp.NET has no company, funding or acquisition history behind it; it is built by a volunteer community that hosts its code on a self-run Forgejo instance and positions the project as a deliberately non-commercial alternative to venture-backed social networks.
Iceshrimp.NET implements the ActivityPub protocol for federation with Mastodon, Misskey, Pleroma and other compatible servers, and also implements the Mastodon client API, so popular apps like Elk, Tusky and Mona work with it out of the box.
Inherited from its Misskey lineage, it supports MFM rich-text formatting, emoji reactions and quote posts, and adds newer capabilities such as TOTP two-factor authentication, full drive and file management, and a configurable HTML-only public preview mode for crawlable, JavaScript-free profile pages.
As open-source, self-hosted software, Iceshrimp.NET carries no license fee; anyone can download and run it on their own server infrastructure at no software cost, with hosting expenses being the only real cost involved.
There is no official managed hosting tier from the project itself, though some community operators run publicly joinable instances that are typically free to join or supported through donations rather than a formal subscription.
Yes, it is free, open-source, self-hosted software with no license fees.
Yes, it implements the Mastodon client API, so apps like Elk, Tusky and Mona can connect to it.
Iceshrimp.NET is a complete rewrite of the original JavaScript-based Iceshrimp in C# on .NET, built for better performance and maintainability.
As of its most recent releases it is still in beta, and developers recommend caution before upgrading existing production instances.
It is maintained by a volunteer open-source community, with no company or venture funding behind it.
Yes, it implements the ActivityPub protocol, allowing federation with Mastodon, Misskey, Pleroma and other compatible servers.