Jauml

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The common library behind NightBeam mods

Jauml (Just Another Utility Minecraft Library) holds the code our mods share: typed JSON configs with comments, server events with a tick scheduler, and one platform API for Fabric, NeoForge and Forge.

Playing? If a mod asks for Jauml, put the jar for your loader and Minecraft version in your mods folder. It adds nothing to the game by itself.

3.0 is available for Fabric, NeoForge and Forge on 1.20.1, 1.21.1, 26.2 and 26.3. Mods built for Jauml 2.x keep working on it.

New: the full documentation, with every API, examples, the migration guide and the changelog, now lives at nightbeam.dev/docs/jauml.

Write your settings as a plain Java class and bind it with JaumlConfig.bind("my_mod", "common", MyConfig.class).

• Comments in the file. @Comment text, @Range bounds, allowed enum values and defaults are written as // lines above each option. Players can add their own comments too; the file still loads.
• Safe loading. Missing options get their defaults, values of the wrong type are converted or reset, and numbers outside their range are clamped, each with a warning in the log.
• Nested sections from nested classes, plus lists and maps. Map entries a player removes stay removed.
• Live updates. reload(), reloadIfChanged(), update(...) and change listeners. A file that breaks while the game runs keeps the last good values; one that breaks before startup is moved to .bak and replaced with defaults.
• Migrations run before binding, so renamed or moved options carry over.

• ServerEvents: starting, started, stopping, stopped, tick start and tick end, for dedicated and singleplayer servers. ServerEvents.currentServer() returns the running server.
• PlayerEvents: join and leave.
• Scheduler: runLater, runRepeating and queueServerWork (the MCreator work queue, same meaning), always on the server thread. Pending tasks are dropped when the server stops.
• One listener works on Fabric, NeoForge and Forge. Start a server with -Djauml.selfTest=true to see every event in the log; the card above shows that log from a NeoForge 26.3 boot.

• Services.load(IMyHelper.class) loads your own loader-specific implementations, so you can delete the copy of the MultiLoader Services class from your mod.
• Platform: the loader, physical client or dedicated server, development environment, game and config directories, the Minecraft version, and the version and name of any loaded mod.
• Version-aware integrations: Platform.isModLoaded("geckolib", ">=4.4") and Platform.isMinecraft(">=26.2").

The 2.x config API is all still here:

• ConfigFile via JaumlConfig.open(...): typed getters, dot paths such as server.port or users[0].name, lists, atomic saves, reload on change and backups of broken files.
• JsonSchema for type, range, enum, length and required-key checks, JsonMigrator for versioned upgrades, and JsonLib for safe parsing, deep merge, normalization and stable output.
• JaumlConfigLib, the static helpers older mods call, keeps every method and signature for the whole 3.x line.

• Cooldowns: per-player (or per-anything) cooldowns on wall-clock time or server ticks.
• Version and VersionRange: compare 1.20.1, 26.3.0.95-beta or 0.165.0+26.3, and check ranges written as [2.1,3), >=2.1 <3, ~2.3, ^2, 1.x or a || b.
• Event: a small listener list with priorities for your own events.

Minecraft	Loaders	Java	Also install
1.20.1	Fabric, Forge	17	Fabric API (Fabric, recommended)
1.21.1	Fabric, NeoForge	21	Fabric API (Fabric, recommended)
26.2 · 26.3	Fabric, NeoForge	25	Fabric API (Fabric, recommended)

• Download the file that matches your loader and Minecraft version, for example jauml-fabric-26.3-3.0.0.jar.
• Install it wherever the mod that needs it is installed: client, server or both.
• On Fabric, configs work without Fabric API; server events and the scheduler need it, and Jauml logs a warning when it is missing. Fabric on 1.20.1 needs Fabric Loader 0.16.10 or newer.
• Updating from 2.x: replace the old jar. Your config files and the mods that use them carry on as before.
• Minecraft 1.21.11 or 26.1.2? Keep Jauml 2.3.1; 3.0 is not built for those versions.

Jauml is on the Modrinth Maven. Use the version number shown on the Versions tab, which ends in your loader and Minecraft version:

repositories {
    maven { url = "https://api.modrinth.com/maven" }
}

dependencies {
    // Fabric 1.20.1 / 1.21.1 and Forge 1.20.1 remap mod jars:
    modImplementation "maven.modrinth:jauml:3.0.0+fabric-1.21.1"
    // NeoForge, and Fabric on 26.x (unobfuscated):
    implementation "maven.modrinth:jauml:3.0.0+neoforge-26.3"
}

Then declare it in fabric.mod.json ("jauml": ">=3.0.0") or neoforge.mods.toml / mods.toml (versionRange = "[3.0.0,)"). The developer setup guide and the migration guide walk through every API with examples.

Does Jauml do anything on its own? No. It is a library: it loads, writes one small demo config in development environments, never in play, and waits for mods that use it.

Do I need it on the server and the client? Install it wherever the mod that requires it is installed. Jauml itself sends nothing over the network.

Will my mods that were built for Jauml 2.x still work? Yes. 3.0 removes nothing from 2.x and changes no signature; a test in the build pins every method released mods call.

Where are the configs? In your config folder, under the folder each mod chose, for example config/my_mod/common.json.

Where are the docs? On our website: Documentation · Typed configs · Server events · Platform · Migration guide · Changelog · Issues

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Jauml is licensed under Apache-2.0. Made by NightBeam Studio.

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Jauml powers every NightBeam mod. Play them together in Remnants: Ashen Legacy, NightBeam's story-driven soulslike RPG modpack.

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