What RunicLib is
RunicLib is a library mod made by Yirmiri. It isn't something you play with directly. It's code that other mods build on. The project page says it's used in many Azurune projects, and that other developers are welcome to use it too.
Its focus is MultiLoader utilities. That means code written to be shared across several mod loaders instead of being rewritten for each one. On top of that, it adds new attributes and new effects.
What it gives modders
The page lists a handful of concrete pieces. There's a common registry method for MultiLoader projects. There's a common flammability method, so a modder doesn't need loader-specific code to make something burn. There are conditional recipes too, which are recipes that depend on a condition being met.
RunicLib also ships premade effects and effect classes. If you're building a mod that needs a status effect, you can start from what's already there. Several of the effect icons were drawn by outside artists, and the page credits them by name.
Finally, it exposes public common classes for MultiLoader projects. These are the shared building blocks you can reference from your own code.
Who it suits
It suits mod developers who target more than one loader and are tired of duplicating basic plumbing. It also suits anyone who already uses an Azurune mod and wants to know what that extra file in the mods folder is.
If you just want new gameplay, this isn't it. RunicLib doesn't claim to add content on its own.
Loaders and Minecraft versions
RunicLib supports Forge, Fabric, Quilt and NeoForge. For Minecraft, it lists 1.20.1 and 1.21.1. Those are two specific versions, so don't assume anything in between is covered.
The project is marked as required on both the client and the server. Plan for it to be present on both sides.
Modpacks and license
The author says you're free to include RunicLib in modpacks or use it as a library for your own projects. This license is listed as LicenseRef-AZURUNE-License. Read the license text itself before you redistribute anything, because the page doesn't spell out its terms.
Support and future plans
Bug reports go on the project's GitHub page. The author asks you to check for an existing report first, so you don't file a duplicate, and to use the proper tags when you can. Suggestions can go to the Azurune Discord server or to GitHub, following the posting guidelines.
As for ports, the author has no plans to go back to older Minecraft versions. For newer versions, they say they'll probably stick with whichever is the biggest modding version at the time, since that's the one they'll be playing on. That's a statement of intent, not a promise of a specific release.
Credits
The page thanks the people who helped with the mod's content. Look, backupCup and Betwixer are credited as the artists behind various effect icons.
Categories
On Modrinth, RunicLib is filed under Game Mechanics, Libraries & APIs, and Magic. The Libraries & APIs tag is the one that matters most here. It tells you this is a tool for developers first.
