Library usage

Use the facade for normal launcher code:

import { MinecraftKit } from "@loontail/minecraft-kit";

const kit = new MinecraftKit();

Facade surface

Namespace	Methods
kit.versions.{minecraft,fabric,forge,runtime}	list, resolve (and latest / get on minecraft)
kit.targets	create, resolve, list
kit.install	plan, run, runtime.{plan,run,standalonePlan}
kit.verify.{minecraft,fabric,forge,runtime,targetReady}	run
kit.repair.{minecraft,fabric,forge,runtime}	plan, run (plus kit.repair.all)
kit.launch	compose, run
kit.auth	authorizationCode.run, refresh
kit.auth.profile	setSkinFromUrl, uploadSkin, resetSkin
kit.cache	get, set, delete, clear

Constructor options

new MinecraftKit({
  httpClient,  // optional — defaults to FetchHttpClient (node fetch)
  cache,       // optional — defaults to createMemoryCache() (LRU, 5-min TTL)
  logger,      // optional — defaults to silentLogger
  system,      // optional — defaults to detectSystem()
  spawner,     // optional — defaults to ChildProcessSpawner
});

Replace dependencies for tests, custom transport, logging, or process supervision.

Symmetric versions API

import { MinecraftChannels, VersionPreference, RuntimePreference } from "@loontail/minecraft-kit";

await kit.versions.minecraft.list({ channel: MinecraftChannels.RELEASE });
await kit.versions.minecraft.resolve({ version: "1.20.1" });

await kit.versions.fabric.list({ minecraftVersion: "1.20.1" });
await kit.versions.fabric.resolve({
  minecraftVersion: "1.20.1",
  preference: VersionPreference.LATEST,
});

await kit.versions.forge.list({ minecraftVersion: "1.20.1" });
await kit.versions.forge.resolve({
  minecraftVersion: "1.20.1",
  preference: VersionPreference.RECOMMENDED,
});

await kit.versions.runtime.list({ system: kit.targets.system });
await kit.versions.runtime.resolve({
  system: kit.targets.system,
  component: "java-runtime-gamma",
  preference: RuntimePreference.RECOMMENDED,
});

Standalone helpers

Import standalone helpers when you do not want the facade:

import {
  verifyMinecraft,
  planMinecraftRepair,
  runRepair,
  planRuntimeInstall,
  MojangAuthApi,
  toOnlineAuth,
  FetchHttpClient,
  createMemoryCache,
} from "@loontail/minecraft-kit";

The facade composes these with the injected dependencies.

Logging

Pass a Logger to the constructor for trace output. The kit ships three implementations:

import { consoleLogger, silentLogger, scopedLogger } from "@loontail/minecraft-kit";

const kit = new MinecraftKit({ logger: scopedLogger(consoleLogger, "launcher") });

scopedLogger(base, scope, baseFields?) prefixes messages with [scope] and merges baseFields into every emission. The auth flow logs through scopedLogger(base, "auth").

Serialising a target

kit.targets.resolve returns a self-contained Target. To reuse it later, persist the same id / directory / minecraft / loader inputs and resolve again. Upstream metadata is fetched again; the kit stores no launcher state.