Anti-duperz
Stops exploiters on your Minecraft SMP from doing any sort of dupe this includes paper dupe, recent 1.21.11 dupe.
📖About Anti-duperz
Anti-Dupe
Compatibility: Bukkit / Spigot / Paper / Purpur (1.21.11)
Key Features
Advanced Item Duplication Prevention (For un-stackable items)
Uses a hybrid system of deterministic hashes and per-item unique IDs to safely detect duplicated items without false positives.
Lineage-Aware Serialization (For stackable items)Players can now combine similar stackable items even when items carry different lineage / NBT data.
Lineage serial ranges are merged correctly
No data is lost
-Inventory consolidation behaves like vanilla Minecraft
Inventory & Cross-Inventory Scanning
Detects duplicate items within a player’s inventory and across all online players.
Keeps legitimate copies and removes only excess items.
Custom Item Rules (Name-Based)Track custom items by display name, not NBT or material, preventing renamed items from bypassing detection.
Per-Item Hash Modes
- NAME – stackable items share a deterministic hash (ideal for currencies like Money Sachets)
- UNIQUE – non-stackable or special items get a unique ID per item
Custom Stack Sizes (Per Item)
Define allowed stack sizes for both vanilla and custom items via commands or config.
Always-Scanned Custom ItemsCustom items are always checked, even when onlyscan mode or material exclusions are enabled.
Multi-Language Support
Added in game language support for the following.
de_DE
en_US
es_ES
fr_CA
fr_FR
it_IT
ja_JP
pl_PL
pt_BR
ru_RU
tr_TR
uk_UA
zh_CN
Safe Removal & Recovery System
- Excess duplicate items are backed up to recovery.yml instead of being deleted.
Multi-Language Discord Webhook Alerts (Embed Messages)
- Sends rich embed notifications in multiple languages to a Discord channel when a duplication is detected.
Admin Whitelist
Exempt trusted players from all anti-dupe checks.
OnlyScan ModeScan only high-value items for performance, while still protecting all custom items.
Automatic Ban OptionOptionally bans players caught duplicating, with full logging.
Hot Reload SupportReload custom item rules, stack sizes, hash modes, language files, and Discord config without restarting the server.
Detailed LoggingDuplication attempts logged in dupe_log.yml, bans recorded in bans.yml.