Chronos Backups

^{The wonderful mod icon and banner were created by Mylèna Yarah Krijnen.}

Chronos Backups is a multi-loader, multi-version Minecraft backup utility. Saves only the most important parts of your world, keeping backups smaller.

Features

• Multi-version, multi-loader architecture (Fabric, NeoForge, Forge, Bukkit, Spigot, Paper, Purpur and Folia).
• Scheduled and manual backups via an in-game /chronos command with a configurable permission level.
• Backups are pruned and filtered to only include the most important parts of your world, keeping backups much smaller than traditional backups.
• Configurable file copy blacklist to exclude specific files and folders from the backup, prefilled with common server-related files and folders.
• Cloud sync: upload finished backups to your cloud provider of choice, and optionally delete them locally after a successful upload. Currently supported: !Google Drive

Commands

Command	Description
/chronos backup	Run a manual backup immediately.
/chronos cancel	Stop the backup currently in progress.
/chronos speedtest <seconds>	Run repeated backups for benchmarking (diagnostic. not for normal use).

The required permission level defaults to 4.

Performance and benchmarks

On default settings, Chronos backups typically shrink to about 1–15% of the original world size. When Distant Horizons and/or Voxy data is filtered out as well, the backup is often under 7% of the full on-disk footprint (world + LOD).

World	Size	Distant Horizon size (256 render distance)	Voxy size (Full world)	Average backup time	Final size (%pruned, %filtered + pruned)
MY 100 DAYS SURVIVAL WORLD (1.19)	189 MB	106 MB	85,8 MB	1,25s	28,0 MB (15%, 7%)
my survival world	4840 MB	888 MB	3060 MB	10,76s	46,5 MB (0.96%, 0.53%)
My survival World (Mission)	1290 MB	630 MB	708MB	4,56s	156 MB (12%, 6%)
My Survival World	1260 MB	501 MB	816 MB	6,68s	29,3 MB (2%, 1%)

Distant Horizons (render distance 256, existing chunks only). Voxy (/voxy import current, existing chunks only).

Method: Minecraft 26.2 Fabric, default Chronos config. Avg. time is mean backup duration over 120 seconds of continuous runs. CPU: AMD Ryzen 7 9800X3D. SSD: Samsung 970 EVO Plus 2TB.

Cloud sync

Chronos can upload finished backups to a remote cloud provider, then optionally remove the local copy.

Behaviour

• Local backups missing from the remote are uploaded, including catch-up after a failed upload or a restart.
• maxStoredBackups also caps how many Chronos backups each enabled provider keeps per world (oldest removed first). Values below 1 disable automatic removal locally and remotely.
• If shouldKeepLocalBackups is false, a backup is deleted from disk (only after it has been uploaded successfully).

When multiple worlds would map to the same remote folder (e.g. two servers both named "world"), Chronos attempts to resolve this by assigning a unique alias in chronos-alias.txt instead of overwriting. This favors safety over storage, so orphaned remote data may remain. Watch the console when enabling cloud sync on multiple servers.

Providers

Currently supported: !Google Drive. Enable it with googleDriveEnabled = true, restart, then follow the authorization URL printed in the console. Sign in once, tokens are stored on that machine under google-drive-tokens/. (Anyone with access to this token will be able to upload and delete backups from your Google Drive. They will not be able to access any other files in your Google Drive.) If you cannot open a browser on the server (for example a headless console), complete the OAuth flow on a local machine, then copy the google-drive-tokens/ folder to the server.

Google Drive was chosen because it is the most popular cloud provider, and has the most generous free tier, with 15GB of storage. OneDrive and Dropbox are planned. They are not available yet.

Limitations

Chronos prioritizes aged world data, chunks that do not yet count as "old enough" can be left out of a backup. If you enter a new chunk, change blocks or items, and a backup runs before that area is included, those changes may be missing from that backup (depending on configuration). That situation is seen as extremely rare and can only cause loss on restore, never duplication.

Supported versions

All currently supported versions are listed below. Chronos is committed to never drop support for a version.

Minecraft	Support	Loader(s)	Backup	Config	Notes
26.x	✅ Supported	Fabric + NeoForge + Bukkit, Spigot, Paper, Purpur and Folia	✅	🟠 File-only	Paper plugin: 26.1.1+ only. Folia: 26.1.2 only.
1.21.x	✅ Supported	Fabric + NeoForge + Bukkit, Spigot, Paper, Purpur and Folia	✅	🟠 File-only	Fabric/NeoForge: pre-1.21.11 vs 1.21.11+ split. Paper plugin: one jar for all 1.21.x. Folia: subset of patches.
1.20.x	✅ Supported	Forge + Fabric + NeoForge + Bukkit, Spigot, Paper, Purpur and Folia	✅	🟠 File-only	Forge: 1.20.0–1.20.1 only. Fabric: 1.20.x. NeoForge: 1.20.2–1.20.6. Paper plugin: all patches except 1.20.3. Folia: subset of patches.
1.19.x	✅ Supported	Fabric + Forge + Bukkit, Spigot, Paper, Purpur and Folia	✅	🟠 File-only	Folia: 1.19.4 only.
1.18.x	✅ Supported	Fabric + Forge + Bukkit, Spigot, Paper and Purpur	✅	🟠 File-only	-
1.17.x	✅ Supported	Fabric + Forge + Bukkit, Spigot, Paper and Purpur	✅	🟠 File-only	Forge: 1.17.1 only.
1.16.x	✅ Supported	Fabric + Forge + Bukkit, Spigot and Paper	✅	🟠 File-only	Paper plugin: 1.16.1+ only.
1.15.x	✅ Supported	Fabric + Forge + Bukkit, Spigot and Paper	✅	🟠 File-only	Fabric + Forge: unified 1.14-1.15.x jar.
1.14.x	✅ Supported	Fabric + Forge + Bukkit, Spigot and Paper	✅	🟠 File-only	Fabric + Forge: unified 1.14-1.15.x jar. Forge: 1.14.2–1.14.4 only.
1.13.x	✅ Supported	Forge + Bukkit, Spigot and Paper	✅	🟠 File-only	Forge: 1.13.2 only. [^2]
1.12.x	✅ Supported	Forge + Bukkit, Spigot and Paper	✅	🟠 File-only	Forge: all 1.12.x patches. Paper plugin: 1.12.2 only. [^2], [^3]
1.11.x	✅ Supported	Forge + Bukkit, Spigot and Paper	✅	🟠 File-only	Forge: 1.11.0, 1.11.2 only. Paper plugin: 1.11.2 only. [^2]
1.10.x	✅ Supported	Forge + Bukkit, Spigot and Paper	✅	🟠 File-only	Forge: 1.10.0, 1.10.2 only. Paper plugin: 1.10.2 only. [^2]
1.9.x	✅ Supported	Forge + Bukkit, Spigot and Paper	✅	🟠 File-only	Forge: 1.9.0, 1.9.4 only. Paper plugin: 1.9.4 only. [^2]
1.8.x	✅ Supported	Forge + Bukkit, Spigot and Paper	✅	🟠 File-only	Forge: 1.8.0, 1.8.8, 1.8.9 only. Paper plugin: 1.8.8 only. [^2]
1.7.x	✅ Supported	Forge + Bukkit, Spigot and Paper	✅	🟠 File-only	Forge: 1.7.10 only. Paper plugin: 1.7.10 only. [^1], [^2]
1.6.x	❌ Unsupported	Forge	❌	🔴 None	[^2]
1.5.x	❌ Unsupported	Forge	❌	🔴 None	[^2]
1.4.x	❌ Unsupported	Forge	❌	🔴 None	[^2]
1.3.x	❌ Unsupported	Forge	❌	🔴 None	[^2]
1.2.x	❌ Unsupported	Forge	❌	🔴 None	-
Beta & Alpha	❌ Unsupported	Babric	❌	🔴 None	Beta & Alpha versions may be supported in the future, but the flagship Chronos feature (world pruning) will be unavailable.

Configuration

The mod's configuration is stored in the config/chronos.toml file. This file is automatically created when the mod is first run, and is located in the config folder. For the forseeable future, there is no GUI configuration available. Config options include:

• backupFolderName: The name of the folder that will contain the backups.
• pruneChunks: Whether chunk pruning is enabled for backups.
• pruneTimeRequirementSeconds: Minimum playtime (in seconds) for a chunk to count toward world pruning.
• pruneMaxWorkerThreads: Maximum worker threads for pruning. 0 (or less) means "auto" (pruner picks a sensible default).
• scheduleBackups: Whether to run backups on a timer.
• backupIntervalSeconds: Seconds between automatic backup runs.
• maxStoredBackups: Maximum backups kept per world locally and on each enabled cloud destination. After a successful backup, oldest local backups are removed if the limit is exceeded. Cloud sync also trims remote Chronos backups to this cap. Recommended value: 5. Values lower than 3 can be used to save space, but risks serious data loss if a catastrophic error occurs. Values below 1 disable automatic removal.
• compressionMethod: Whether to compress the backups into a zip file or store it as an uncompressed folder. Accepts "zip" or "none".
• googleDriveEnabled: Enable Google Drive as a cloud sync destination (see Cloud sync).
• shouldKeepLocalBackups: When true, keep local backups after a successful cloud upload. When false, delete each local backup once it has been uploaded.
• commandRequiredPermissionLevel: Permission level required to run /chronos.
• copyBlacklist: Folders and files to exclude from the backup.

This list may be out of date. To see the latest available configuration options and their descriptions, see ChronosTomlSpec.java.

Nightly releases

Github Actions automatically builds and uploads nightly releases to the GitHub Releases page. These are not the same as stable releases found on Modrinth, CurseForge or Github Releases, and should not be relied upon or assumed to be stable.