🧰 DevKit API 0.2.0-alpha.4

A maintenance and tooling release: registry lookup, targeted config synchronization, runtime diagnostics, and cross-version tag generation.

DevKit API is a lightweight library for Fabric mod developers. It provides reusable tools for registries, networking, Data Components, synchronized configuration, and data generation, without adding gameplay content of its own.

✨ Highlights

Registry Lookup

Declared entries can be resolved again by path, which helps when registration and use live in different classes:

• KRegister.get(path) returns Optional<RegistrySupplier<T>>, empty for unknown paths;
• KRegister.contains(path) reports whether a path was declared;
• KRegister.size() reports how many entries a container holds;
• all three work before bootstrap() runs, and the supplier stays unbound until it completes.

Targeted Config Synchronization

Configuration synchronization is no longer limited to a full broadcast:

• ConfigSyncManager.sendTo(player, configId) pushes one configuration to a single player;
• non-authoritative configurations are refused, matching the client-side check that already rejected them on arrival;
• ConfigManager.delete(modId, name) removes a configuration file and reports whether one was removed;
• applying a synced config on the client is logged at info level with the number of fields written, so synchronization is observable without a debugger.

Runtime Diagnostics

The all-in-one artifact registers one read-only status command, /devkit info. It reports the installed DevKit version, networking capabilities, the number of registered packets, how many declared registry entries are bound, and the number of synchronized configs.

DevkitCore.getApiVersion() and DevkitCore.getModVersion() expose the same information programmatically, which is useful for crash reports and support requests.

Tag Generation Across Versions

The vanilla tag provider API changed twice between 1.21.1 and 1.21.11. TagHelper now hides both renames behind a single hook:

• override buildTags() instead of the version-specific provider hook;
• add(key, entries...) and addOptional(key, entries...) write identifiers directly, with no need to resolve a registry key first;
• tag(path) and cTag(path) build namespaced and convention tag keys;
• overriding the provider hook directly still works, so existing code keeps compiling.

One provider source file now compiles unchanged on 1.21.1, 1.21.8 and 1.21.11.

🔧 Fixes

• Config sync initialization: the synchronization payload and the player join listener are initialized on demand. Server-authoritative configs reach clients even when the sync manager is never initialized explicitly. Previously a config could be registered and then silently never sent.
• Config path validation: segments that start with a dot are rejected instead of resolving outside config/<modId>.
• Client initialization failures: reported as errors, so a missing client packet receiver is no longer hidden behind a debug message.
• devkit-core dependencies: the module declares its Fabric API dependency. Installing a module without Fabric API now fails with a dependency error instead of a class loading failure during startup.
• ModelGen.simpleItem: logs a warning instead of silently skipping identifiers that are not registered.
• Config sync logging: the manager no longer logs a misleading zero config count on startup.

📦 For Developers

Dependent mods can consume DevKit API through Modrinth Maven:

repositories {
    maven { url = "" rel="noopener nofollow" target="_blank">https://api.modrinth.com/maven/" }
}

dependencies {
    modImplementation "maven.modrinth:devkitapi:0.2.0-alpha.4+1.21.1"
}

Maven Local publishing remains available as a fallback. See the README for full setup instructions.

Alpha software. Public API signatures may still change before 1.0.