MezzConfig
by mezz
With MezzConfig, mod developers get a single configuration API for client preferences, per-world settings and server-owned options on Fabric, Forge and NeoForge.
What it does
The library handles three configuration scopes: client preferences that apply everywhere, client settings tied to a single world or server, and configuration owned by the server and synchronized to connected players. Mods built on it use the same API across all three scopes.
Pack authors can supply default values, and players or worlds can still override individual settings. The library ships with checks for typical value kinds, including colors and custom types, and change listeners and restart requirements tell a mod when a setting should take effect. Changes to config files are detected and applied in-game, and migration tools keep existing values when a mod renames or moves its config.
MezzConfig is open source under the MIT License and requires Fabric API. Either side can run it, and neither needs it, so it works on a client alone, a server alone or both. Files exist for 1.19.2, 1.20.1, 1.21.1, 1.21.11, 26.1.2, 26.2 and 26.3, and the latest build, 0.6.8 for 26.3, is in the beta channel.
Key features
Three configuration scopes
Client preferences that apply everywhere, client settings tied to one world or server, and server-owned configuration each have their own storage.
Modpack defaults
Pack authors set default values that players and worlds can override one setting at a time.
Validated value types
Typical kinds such as colors, enums and lists, plus custom types, are checked when they are read and written.
Change listeners and restart flags
A mod can react to a changed setting at once, or mark it as needing a restart.
Live file updates
Edits to config files are detected and applied while the game is running.
Migration and recovery
Tools keep existing settings when a mod changes a config name, location or format.
Compatibility
Latest build for each game version and loader.
Only full game releases are shown. This mod publishes no snapshot builds.
Requirements
Dependencies declared by the latest file for each loader.
Required 1
Required by 2 mods
Use cases
Mod developers
Developers replace separate config code with one API that covers every scope and loader.
Modpack authors
Pack authors ship sensible defaults and still let players change the settings they care about.
Who it’s for: Mod developers writing configurable mods for Fabric, Forge or NeoForge, and modpack authors who set default options for a pack. Setup instructions and API examples are on GitHub.
Questions
Does MezzConfig need to be installed on both sides?
Which loaders does MezzConfig support?
Does MezzConfig require another mod?
In the catalog
MezzConfig is one of 3,514 Library mods on ModsFinder, and one of 2,348 Library mods for Fabric. 8,071 mods support Minecraft 26.3.
More from mezz
Similar mods
What the author says
MezzConfig is a lightweight configuration library for Minecraft mods on Fabric, Forge, and NeoForge. It gives mod developers one API for managing client preferences, settings for individual worlds and servers, and server-controlled options synchronized to connected players. Mod developers can find setup instructions…
Official listing
- Modrinth page
- modrinth.com/mod/mezzconfig
- Owner
- mezz
- Published
- 2026-09-10
- Updated on Modrinth
- 2026-10-03
- Facts verified
- 2026-10-15