Backups

First public build. Working and verified on a live Paper 26.2 server, but still a beta — see the limits at the bottom before you rely on it.

What it does

• Scheduled and manual backups of every loaded world
• Incremental — files whose size and modification time are unchanged are never re-read. A second backup of an idle world wrote 421 bytes instead of 2.1 MB in testing.
• Deduplicated — files are stored under a hash of their contents, so identical region files across snapshots and worlds are stored once
• Verified restores — every file is hash-checked before it is written back, and /backup verify checks a snapshot is restorable before you need it
• Off the main thread — worlds are flushed on the main thread, then all walking, hashing and copying happens in the background
• Restore rebuilds into a separate folder and never touches your live world

Commands

/backup now · /backup list · /backup verify <snapshot> · /backup restore <snapshot> · /backup status — permission backup.admin

Known limits

• No automatic pruning yet. Snapshots are kept until you delete them. Deduplication means only changed data adds to the store, but it still grows.
• Backups are local. No off-site upload — copy them elsewhere yourself.
• Restore is whole-world only, and requires stopping the server to swap in.
• Paper 26.2+ and Java 25 only. Untested on Spigot and Folia.

Please don't make this your only backup yet. Bug reports very welcome.