Chunkis

Chunkis

Chunkis is hosted on Modrinth.

Please use the Modrinth page for downloads, updates, and project information:

https://modrinth.com/mod/chunkis

This CurseForge page is only here to redirect users to the official Modrinth listing.

Smaller worlds. Lighter saves. Same game.

Worlds grow quietly. Every chunk you explore, every chest, every mob ends up on disk, and over time that makes backups, uploads and long-term storage much heavier than they need to be.

Chunkis gives Minecraft a smarter way to save your world: smaller on disk, lighter on your game, and careful never to lose your data.

What Chunkis does

Chunkis replaces how Minecraft stores chunks with its own compact format. It:

• packs your world tighter, so the same world takes less space on disk;
• saves in the background, keeping the heavy lifting away from your game;
• brings back recently visited areas fast, without rebuilding them from scratch;
• restores everything when chunks load: blocks, chests and other block entities, mobs and other entities;
• never overwrites what it can't read, so a problem never turns into lost data;
• converts existing vanilla worlds automatically when you open them;
• works in singleplayer and LAN worlds.

Chunkis only changes how your world is stored. It doesn't add content, change recipes or touch rendering.

Why use it?

Requirements

• Minecraft 1.21.11
• Fabric Loader
• Fabric API
• Java 21 or newer

Installation

1. Install Fabric Loader for Minecraft 1.21.11.
2. Download Fabric API and Chunkis, here on Modrinth or from GitHub Releases.
3. Put both .jar files in your .minecraft/mods folder.
4. Back up your world, then launch with the Fabric profile.

Important: beta software

Chunkis is in beta. Before using it on a world you care about:

1. Make a complete backup of your world.
2. Try it on a copy or a new world first.
3. Restart the world and check your blocks, chests, mobs and dimensions.
4. Keep the backup until you're happy with the result.

Switching to Chunkis is one-way. Removing the mod doesn't turn your world back into a vanilla save. To go back, restore the backup you made before switching.

Existing worlds

Open an existing world with Chunkis installed and it converts automatically.

The conversion covers both your chunks and your entities. Every original vanilla file is backed up and verified before it's retired, and if any chunk fails to convert, the world doesn't open. You never end up with a half-converted world.

Compatibility

• Singleplayer and LAN worlds: supported.
• Dedicated servers: not tested yet, and existing worlds can't be converted on a dedicated server yet. If you try it, back up first.
• Other storage mods: Chunkis hasn't been tested with mods that change how chunks are saved or loaded, such as other storage, compression or chunk-loading mods. Back up first, and please report any conflicts.

Storage impact

World size: a freshly explored 2000 × 2000 block area, seed 0. The whole world folder, entities included.

Playing: the same world explored, edited and saved over and over, with and without Chunkis.

How much you save depends on your world: its terrain, how many chests and mobs it has, how much you've built, and which other mods you run. Got numbers from a real played world? Share them.

Why are these numbers lower than in older versions? Earlier versions didn't save chunks you never changed; they regenerated them from the seed every time you came back. That made fresh worlds look tiny on disk (88% smaller in our old benchmark) but cost CPU and lag on every load. Chunkis now saves every chunk, so returning to an area is faster and smoother.

FAQ

Will Chunkis improve FPS or TPS?

FPS stays the same; Chunkis doesn't touch graphics. Saving and loading get lighter, though: your game uses less memory and less CPU, and big saves cause shorter lag spikes. Everyday tick times stay about the same.

Is my world always smaller?

Not guaranteed, but in our tests it was around 30% smaller. See Storage impact.

Does Chunkis change gameplay?

No. It only changes how your world is saved and loaded.

Can I use it on my existing world?

Yes. It converts automatically when you open the world. Back up first; see Important: beta software.

Does it work on dedicated servers?

Not tested yet. Chunkis is confirmed for singleplayer and LAN worlds. If you try a dedicated server, back up first.

Can I go back to vanilla?

Not automatically. Restore the backup you made before switching.

I found a problem. What now?

Report it on GitHub with your Minecraft and Fabric versions, your full mod list, the steps to reproduce it, and your latest.log (plus the crash report if there is one).

Report a bug · Documentation · Source code

License: MIT