RemapIDs
RemapIDs is a data-driven registry remap and alias system for modpack developers. Define JSON mappings that redirect item, block, entity, fluid, tag, recipe, and loot table IDs to alternative IDs at runtime — enabling seamless world migration when mods are removed, replaced, or reorganized.
Key Features
| Feature | Description |
|---|---|
| Wildcard Expansion | Use * patterns to remap entire families of IDs in a single entry |
| Type Filtering | Optionally limit which remap types (block, item, recipe, etc.) a mapping applies to |
| Chain Flattening | Automatically resolves multi-step chains (A→B, B→C becomes A→C) |
| Circular Detection | Rejects circular mappings with clear error logging |
| Tag Remapping | Redirect tag references with the # prefix, including tag-to-item conversion |
| Multi-File Configs | Organize remaps across multiple JSON files, processed alphabetically |
Supported Platforms
| Loader | Minecraft Version | Status |
|---|---|---|
| Forge | 1.20.1 | Supported |
| Fabric | 1.20.1 | Supported |
| Fabric | 1.21.1 | Supported |
| NeoForge | 1.21.1 | Supported |
How It Works
RemapIDs operates through two categories of remaps:
- Registry remaps (block, item, fluid, entity_type) are injected at registry freeze time, before the world loads. These require a full game restart to apply.
- Reloadable remaps (tag, recipe, loot_table) are applied when datapacks load and can be refreshed with
/reload.
There are no in-game commands or UI — RemapIDs is configured entirely through JSON files placed in config/remapids/remaps/.
Next Steps
- Getting Started — Install the mod and create your first remap
- Configuration Reference — Full reference for the JSON config format
- Examples — Real-world modpack migration scenarios