ProbablyBackpacks

✦ Probably Backpacks ✦

Tiered Backpack System with Upgrades for Spigot & Paper

Leather · Copper · Iron · Gold · Diamond · Netherite

Custom Textures · Upgradeable · 3D Models · CuriosPaper Addon

Think of it as Sophisticated Backpacks — but for Paper & Spigot, with 3D models, rich upgrades, and a seamless accessory integration.

# CAUTION

### ⚠️ NO NEW CONTENT UPDATES FOR THIS VERSION

This standard version of Probably Backpacks is feature-locked and will NOT receive any new content updates or features. It will only receive maintenance updates to maintain compatibility with newer Minecraft/Paper releases.

⚜️ Want new features, security, party storage, and advanced upgrades?

Upgrade to Probably Backpacks Premium on BuiltByBit to get access to:

- 🔑 PIN-Pad Security Locks — Prevent pickpocketing with a 4-digit code GUI

- 👥 Synchronized Party Storage — Link backpacks across teammates in real-time

- 🍳 Smart Auto Smelter — Intelligently route items to furnace/smoker/blast modules

- 🧪 XP Sponge & Auto Repair — Absorb XP orbs and auto-repair durability

- 🛢️ Fluid Tank Upgrade — Store up to 10 buckets of fluid

- ⚡ Auto Sort Upgrade & 🛡️ Whitelist Filters

- 🕵️ Stealth Pickpocketing & 🎨 Custom 3D Cosmetic Skins

👉 Click here to get Probably Backpacks Premium on BuiltByBit!

✦ What is Probably Backpacks? ✦

Probably Backpacks adds a complete tiered backpack system to your Minecraft server. Players craft backpacks from Leather all the way up to Netherite — each tier offering more storage and more upgrade slots.

Backpacks are equipped in the CuriosPaper Back slot and are visible on the player's back as a 3D model! This plugin is a CuriosPaper addon, hooking into the accessory system to provide a seamless experience with custom textures, real-time dyeing, and a powerful upgrade system.

This plugin requires CuriosPaper to function!

🚀 What's New in v2.4

• 📥 Autonomous Pickup Task (PickupTask): Dedicated background task for the Pickup Upgrade that checks a 1.5-block radius around players to collect nearby item drops directly into active backpack storage (smartly skips duplicate work if MagnetTask is active).
• 🛠️ Modern Paper & 1.21.4+ Version Parsing: Overhauled VersionUtil with regex matching to support Paper build version strings (e.g., 26.2.build.48-alpha) with automatic fallback to Bukkit.getVersion().
• 🔒 Robust Item & Component Sanitization: Added multi-layered fallback deserialization in BackpackData to strip unregistered/legacy enchantments and invalid item components cleanly.
• ⚙️ GUI Slot Bounds Protection: Added slot boundary safety checks during inventory click processing.

✦ Features ✦

🎒 Core Backpack System

Feature · Description
🎒 · 6 Backpack Tiers · Leather → Copper → Iron → Gold → Diamond → Netherite
📦 · 27 to 120 Slots · Scale from a small pouch to a massive storage vault
⬆️ · 19+ Upgrades · Crafting, Magnet, Cooking, Anvil, Jukebox, Tool Swapper & more
🎨 · Real-time Dyeing · Over 16 colors with live 3D model updates
🧟 · Mob Drops · Mobs can spawn wearing backpacks — loot them for extra storage
👀 · 3D Models · Visible on the player's back with auto-hide when looking down
🔑 · Hotkey Support · Open your backpack with a double-sneak combo — no commands needed
🗄️ · Massive Stacks · Stack items up to 1024 with Netherite Stack Upgrades

✦ Backpack Tiers ✦

Tier · Slots · Upgrade Slots · Key Material
🟤 Leather Backpack · 27 · 1 · Leather + String + Chest
🟠 Copper Backpack · 45 · 2 · Copper Ingots + Leather Backpack
⚪ Iron Backpack · 54 · 3 · Iron Ingots + Copper Backpack
🟡 Gold Backpack · 81 · 4 · Gold Ingots + Iron Backpack
🔵 Diamond Backpack · 108 · 5 · Diamonds + Gold Backpack
🟣 Netherite Backpack · 120 · 6 · Smithing Table + Netherite Ingot

Each tier requires the previous backpack as an ingredient — creating a natural progression chain!

✦ Upgrades ✦

Upgrades are placed into the backpack's upgrade slots to grant powerful abilities:

🛠️ Utility Upgrades

Upgrade · Effect
🔧 Crafting Station · Open a portable crafting table from within your backpack
🔨 Anvil Upgrade · Portable anvil for repairing items on the go
🎵 Jukebox Upgrade · Play music discs directly from your backpack
🛠️ Smithing Upgrade · Portable smithing table for gear progression
⚔️ Tool Swapper · Automatically swaps to the best tool for the block you're mining

🧺 Automation Upgrades

Upgrade · Effect
📥 Pickup Upgrade · Dedicated background task (PickupTask) that collects dropped items within a 1.5-block radius into your backpack
🧲 Magnet Upgrade · Pull nearby items directly into your backpack
🍖 Feeding Upgrade · Auto-feed the player using food stored in the backpack
🔄 Refill Upgrade · Auto-refill hotbar items from the backpack as they are used
📦 Compacting Upgrade · Automatically compress items into blocks (e.g. Iron Ingots → Iron Block)

🍳 Cooking Upgrades

Upgrade · Effect
🔥 Smelting Upgrade · Portable furnace that smelts items while you walk
💨 Blasting Upgrade · High-speed smelting for ores
🍖 Smoker Upgrade · Rapid cooking for food items

🗄️ Storage Upgrades

Upgrade · Effect
🛠️ Upgrade Base · The fundamental component used to craft all other upgrades
🟠 Copper Stack · Increases max stack size of items in the backpack to 96
⚪ Iron Stack · Increases max stack size of items in the backpack to 128
🟡 Gold Stack · Increases max stack size of items in the backpack to 256
🔵 Diamond Stack · Increases max stack size of items in the backpack to 512
🟣 Netherite Stack · Increases max stack size of items in the backpack to 1024

✦ Dyeing & Mobs ✦

🎨 Dyeing System

Express yourself with over 16 unique colors! Leather backpacks can be dyed directly within the backpack inventory.

• Simple Dyeing: No complex GUIs! Simply drop any Minecraft dye onto the dye button in the backpack interface.
• Remove Color: Use a Water Bucket on the dye button to clear the color.
• Live Updates: The 3D model on your back updates instantly when you change the color.

🧟 Mob Drops

Backpacks aren't just for players anymore! Zombies and Skeletons have a small chance to spawn wearing a backpack.

• Visual Models: You can see exactly which tier of backpack a mob is wearing.
• Lootable: Defeat the mob for a chance to collect their backpack!
• Configurable: Adjust spawn rates and which tiers mobs can carry in the config.yml.

✦ Recipes ✦

🎒 Backpack Recipes (click to expand)

🟤 Leather Backpack

Slots: 27 · Upgrade Slots: 1

The starting tier backpack. Requires basic materials to craft.

String · Leather · String
String · Chest · String
Leather · Leather · Leather

🟠 Copper Backpack

Slots: 45 · Upgrade Slots: 2

An upgrade from leather — requires copper ingots and a Leather Backpack.

Copper Ingot · Copper Ingot · Copper Ingot
Copper Ingot · 🟤 Leather Backpack · Copper Ingot
Copper Ingot · Copper Ingot · Copper Ingot

⚪ Iron Backpack

Slots: 54 · Upgrade Slots: 3

Solid mid-tier storage. Requires iron ingots and a Copper Backpack.

Iron Ingot · Iron Ingot · Iron Ingot
Iron Ingot · 🟠 Copper Backpack · Iron Ingot
Iron Ingot · Iron Ingot · Iron Ingot

🟡 Gold Backpack

Slots: 81 · Upgrade Slots: 4

High-capacity storage with plenty of room for upgrades.

Gold Ingot · Gold Ingot · Gold Ingot
Gold Ingot · ⚪ Iron Backpack · Gold Ingot
Gold Ingot · Gold Ingot · Gold Ingot

🔵 Diamond Backpack

Slots: 108 · Upgrade Slots: 5

Premium-tier storage. Only one step away from the ultimate backpack.

Diamond · Diamond · Diamond
Diamond · 🟡 Gold Backpack · Diamond
Diamond · Diamond · Diamond

🟣 Netherite Backpack

Slots: 120 · Upgrade Slots: 6

The ultimate backpack. Features fire and lava immunity (won't burn when dropped). Crafted at a Smithing Table using the Netherite Upgrade template.

Component · Item
Template · Netherite Upgrade Smithing Template
Base · 🔵 Diamond Backpack
Addition · Netherite Ingot

⬆️ Upgrade Recipes (click to expand)

🛠️ Upgrade Base

The fundamental component for crafting most upgrades.

String · Iron Ingot · String
Iron Ingot · Leather · Iron Ingot
String · Iron Ingot · String

🔧 Crafting Station

Adds a portable crafting table to your backpack.

Oak Planks · Crafting Table · Oak Planks
Oak Planks · 🛠️ Upgrade Base · Oak Planks
Oak Planks · Crafting Table · Oak Planks

📥 Pickup Upgrade

Auto-collects picked-up items into the backpack.

Piston
String · 🛠️ Upgrade Base · String
Redstone · Redstone · Redstone

🧲 Magnet Upgrade

Pulls nearby items directly into your backpack. Requires the Pickup Upgrade.

Ender Pearl · Iron Ingot · Ender Pearl
Iron Ingot · 📥 Pickup Upgrade · Iron Ingot
Redstone · Diamond · Lapis Lazuli

🍖 Feeding Upgrade

Auto-feeds the player using food stored in the backpack.

Golden Carrot
Golden Apple · 🛠️ Upgrade Base · Glistering Melon Slice
Ender Pearl

🔄 Refill Upgrade

Auto-refills hotbar items from the backpack as they deplete.

Ender Pearl
Iron Ingot · 🛠️ Upgrade Base · Iron Ingot
Redstone · Chest · Redstone

📦 Compacting Upgrade

Auto-compresses items into their block forms.

Iron Ingot · Piston · Iron Ingot
Piston · 🛠️ Upgrade Base · Piston
Redstone · Piston · Redstone

⚔️ Tool Swapper

Auto-swaps to the best tool for the block you are mining.

Redstone · Wood Sword · Redstone
Wood Pick · 🛠️ Upgrade Base · Wood Axe
Iron Ingot · Wood Shovel · Iron Ingot

🔨 Anvil Upgrade

Adds a portable anvil to your backpack.

Anvil · Diamond · Anvil
Iron Ingot · 🛠️ Upgrade Base · Iron Ingot
Chest

🎵 Jukebox Upgrade

Play music discs directly from your backpack's GUI.

Jukebox
Iron Ingot · 🛠️ Upgrade Base · Iron Ingot
Redstone

🛠️ Smithing Upgrade

A portable Smithing Table for your backpack.

Smithing Table
Iron Ingot · 🛠️ Upgrade Base · Iron Ingot
Chest

🔥 Smelting Upgrade

Smelts items automatically while you travel.

Redstone · Iron Ingot · Redstone
Iron Ingot · 🛠️ Upgrade Base · Iron Ingot
Redstone · Furnace · Redstone

💨 Blasting Upgrade

High-speed smelting for ores and materials.

Redstone · Iron Ingot · Redstone
Iron Ingot · 🛠️ Upgrade Base · Iron Ingot
Redstone · Blast Furnace · Redstone

🍖 Smoker Upgrade

Rapidly cooks food items while you're on the move.

Redstone · Iron Ingot · Redstone
Iron Ingot · 🛠️ Upgrade Base · Iron Ingot
Redstone · Smoker · Redstone

🟠 Copper Stack Upgrade

Increases max stack size in the backpack to 96.

Copper Block · Copper Block · Copper Block
Copper Block · 🛠️ Upgrade Base · Copper Block
Copper Block · Copper Block · Copper Block

⚪ Iron Stack Upgrade

Increases max stack size in the backpack to 128.

Iron Block · Iron Block · Iron Block
Iron Block · 🟠 Copper Stack Upgrade · Iron Block
Iron Block · Iron Block · Iron Block

🟡 Gold Stack Upgrade

Increases max stack size in the backpack to 256.

Gold Block · Gold Block · Gold Block
Gold Block · ⚪ Iron Stack Upgrade · Gold Block
Gold Block · Gold Block · Gold Block

🔵 Diamond Stack Upgrade

Increases max stack size in the backpack to 512.

Diamond Block · Diamond Block · Diamond Block
Diamond Block · 🟡 Gold Stack Upgrade · Diamond Block
Diamond Block · Diamond Block · Diamond Block

🟣 Netherite Stack Upgrade

Increases max stack size in the backpack to 1024.

Netherite Block · Netherite Block · Netherite Block
Netherite Block · 🔵 Diamond Stack Upgrade · Netherite Block
Netherite Block · Netherite Block · Netherite Block

✦ Stats & Suppor