World Backup

Simple, reliable world backups at the press of a key — or the tip of a command.

Ever had your world corrupted by a rogue mod, a power outage, or just a bad decision with WorldEdit? World Backup lets you create instant, compressed zip backups of your entire world folder with a single command. Backups run asynchronously so your server never freezes, and automatic rotation keeps your disk from filling up.

✨ Features

Instant backups — Create a full `.zip` backup of your world with `/backup <name>`
Non-blocking — Backups run on a separate thread; your server stays responsive
Automatic rotation — Old backups are pruned automatically based on a configurable limit
Configurable — Set your backup limit via command or JSON config file
Safe by default — Name validation prevents path traversal attacks
Conflict-friendly — Copies your world to a temp directory first, then zips from the clean copy. Files locked by other mods (Sable, etc.) are retried automatically with increasing backoff.
Server-wide broadcast — All players see backup progress and completion messages.

📋 Commands

`/backup <name>` | Creates a timestamped zip backup with the given name.
`/backuplimit <number>` | Sets the maximum number of backups to keep (1–1000)

Examples:

/backup before-portal → before-portal_2025-06-03_21-30-00.zip
/backup vanilla-test → vanilla-test_2025-06-03_21-31-15.zip
/backuplimit 25 → Sets the rotation limit to 25 backups

All players can use these commands by default — no operator permissions required.

⚙️ Configuration

The backup limit is stored in `backup/backup_config.json` inside your server directory. It is created automatically on first use and can be edited directly:

json {"backupLimit": 10}

The limit can also be changed in-game with `/backuplimit <number>`.

📁 Where are backups stored?

Backups are saved to the `backup/` folder inside your server directory (next to your world folders). Each backup is a compressed `.zip` file named in the format:

<name>_<YYYY-MM-DD_HH-mm-ss>.zip

🔄 Compatibility

World Backup is designed to coexist peacefully with other mods:

Sable — Fully compatible. World files are copied to a temporary directory before zipping, so Sable's file locks don't interfere. Retried up to 5 times with increasing backoff.
Ice and Fire, Dread Land, and other dimension mods — All sub-levels and custom dimensions are
backed up.
Any file-locking mod — The copy-first strategy combined with retry logic handles files locked by other mods without skipping data.
Any world type — Works with vanilla, modded, and custom world formats.

🛠 Technical Details

Copy-first strategy — World folder is copied to a temp directory using `Files.copy` (path-to-path), which on Windows uses the `CopyFileEx` API to handle locked files
Backups flush all chunks to disk before copying (`saveAllChunks`)
Asynchronous execution via `CompletableFuture` — no server tick lag
Automatic retry with backoff (up to 5 attempts) for temporarily locked files
Temp directory is cleaned up automatically after backup completes (even on failure)
Backup rotation deletes the oldest files first by modification time
Safe filename validation: only letters, numbers, hyphens, and underscores allowed

📦 Installation

Install NeoForge for Minecraft 1.21.1+
Drop `worldbackup-1.0.0.jar` into your `mods/` folder.
Start the server — backups are ready to go/

No configuration needed to get started. Just `/backup my-backup` and you're set.

Fast Async Backups