What oωo (owo-lib) works with.
| Platform | Java Edition |
|---|---|
| Loaders | Fabric, NeoForge, Quilt |
| Minecraft versions | 1.18.2, 1.19.4, 1.20.1, 1.21.1, 1.21.8, 1.21.10, 26.1, 26.2 |
| Environment | Client, Server |
owo-lib (stylized oωo) is a Fabric and Quilt utility library that other mods lean on for in-game config screens, particle effects, and networking helpers. It shows up as a dependency error naming owo-lib specifically when a mod built with owo-config or owo-ui needs it and it is not installed. Fabric and Quilt builds track the current 26.2 drop, and the library is required on both the client and the server.
What owo-lib does
Built by glisco03 and the wisp-forest team, owo-lib bundles pieces mod authors would otherwise write themselves. None of it is content a player sees on its own; owo-lib only does something once another mod calls into it.
- owo-ui, a declarative library for building custom in-game screens
- owo-config, a settings screen built on owo-ui with client-server sync
- A networking layer with automatic serialization and particle event triggers
- Item group tab extensions and rich text translations
Installation
Drop the matching owo-lib jar into the mods folder alongside Fabric API, which owo-lib requires. There is no separate client or server download: the same jar goes on both sides, since a mod that depends on owo-lib will not load with it missing from either. Match the owo-lib build number to your Minecraft version and loader; a build made for an older release will not load on a newer one.
Fabric, Quilt, and NeoForge support
owo-lib publishes separate builds per loader, and they do not move at the same pace. Fabric and Quilt builds reach the current 26.2 drop. A NeoForge build exists too, but it stopped at 1.21.10, the last release before Minecraft moved to year.drop versioning, and there is no NeoForge build for the 26.x line yet. Check the loader and version columns on the download page before picking a jar.
Frequently asked questions
Questions about oωo (owo-lib).
5 questions
What mods need owo-lib?
Any mod that lists owo-lib as a dependency, most often ones built with owo-ui for their menus or owo-config for their settings screen. The error naming owo-lib appears at launch when the dependency is missing or on the wrong loader. Installing the matching owo-lib jar for your Minecraft version and loader resolves it.
What is the owo config screen?
It's the in-game settings screen owo-config generates for a mod that uses it, usually reachable from the mod's entry in Mod Menu. Owo-config also saves the settings file and, for mods that need it, syncs settings between client and server automatically. The screen itself belongs to whichever mod built it; owo-lib only supplies the framework behind it.
How do I install owo-lib?
Download the version matching your Minecraft release and loader from Modrinth, then place the jar in the mods folder next to Fabric API. owo-lib runs on both the client and the server, so a multiplayer server needs the same jar installed as well.
Does owo-lib work with NeoForge?
A NeoForge build exists, but it stopped receiving updates at 1.21.10. Fabric and Quilt are the actively maintained targets and reach the current 26.2 drop. A mod that only ships a Fabric or Quilt build will not run against the NeoForge build regardless of Minecraft version.
Is owo-lib safe to use on multiplayer servers?
owo-lib is MIT licensed and sourced from its own Modrinth listing, with the same jar required on both the client and the server for any mod that depends on it. It adds no gameplay content of its own, only library code other mods call into, so it carries no separate server-side risk beyond the mods that use it.
