@opys/curseforge

CurseForge mod-file plugin — resolves a list of CurseForge file references (numeric IDs or /files/<id> URLs) into downloadable Artifacts via the CurseForge API.

npm install @opys/curseforge

import { defineConfig } from '@opys/dev';
import { forge } from '@opys/forge';
import { curseforge } from '@opys/curseforge';

export default defineConfig({
  output: 'opys.json',
  plugins: [
    forge('1.20.1-best'),
    curseforge({
      token: process.env.CURSEFORGE_TOKEN,
      path: (info) => `\${game_directory}/mods/${info.filename}`,
      files: [
        238222, // Just Enough Items
        'https://curseforge.com/.../files/5847', // JourneyMap
      ],
    }),
  ],
});

Requires a CurseForge API key passed as token (or via the CURSEFORGE_TOKEN env var that the opys integration tests use).

Modpacks

curseforgeModpack({ token, file }) is the all-in-one modpack plugin. Point it at a CurseForge modpack file and it does everything: downloads and parses the pack's manifest.json, detects the Minecraft version and mod loader, stands up the matching loader (Fabric / Forge / NeoForge — which already bundles vanilla), installs every mod file, and extracts the pack's overrides/.

import { defineConfig } from '@opys/dev';
import { curseforgeModpack } from '@opys/curseforge';
import { java } from '@opys/java';

export default defineConfig({
  output: 'opys.json',
  plugins: [
    curseforgeModpack({
      token: process.env.CURSEFORGE_TOKEN,
      file: 1040985, // a modpack's CurseForge file id or /files/<id> URL
    }),
    java('17'),
  ],
  manifest: {
    command: ({ curseforgeModpack }) => curseforgeModpack.command,
    args: ({ curseforgeModpack }) => [
      curseforgeModpack.jvmArgs,
      curseforgeModpack.mainClass,
      curseforgeModpack.gameArgs,
    ],
    workdir: '${game_directory}',
  },
});

Every supported loader exposes the same launch groups, so the manifest block is loader-agnostic — the same config launches a Fabric, Forge, or NeoForge pack. Notes:

• Token required at build time (each file is resolved by ID through the authenticated API); the resulting URLs are public, so opys launch against a built manifest needs none.
• Java is separate. Add java(...) yourself (match the major version the pack's Minecraft release needs).
• The manifest's files go to mods/; everything else (resourcepacks, configs) ships in overrides/.
• Quilt packs are unsupported — opys has no Quilt loader plugin.

Part of the opys toolkit; re-exported by @opys/minecraft.