Iceshrimp
A Fediverse server software that began as a fork of Misskey/Firefish but was then rewritten to be more maintainable and resource-efficient. Part of the "Misskey family" of platforms with emoji reactions and rich formatting.
Background: Firefish (formerly Calckey) lost momentum, which spawned several forks — Iceshrimp became one focused on code quality and low resource use for small instances. A complete rewrite ("Iceshrimp.NET") in C#/.NET was underway to leave the heavy Node.js legacy behind. Misskey-style features: custom emoji reactions (not just likes), Markdown-like "MFM" formatting, quote posts. Federates with Mastodon and others via ActivityPub. Niche but illustrates Fediverse dynamics: when a project stagnates, the community splinters into forks that keep experimenting.