🏪 Swells Marketplace

A fully player-driven economy for modern Minecraft modpacks

Swells Marketplace is a secure, scalable, and exploit-resistant marketplace system designed for large modpacks and long-running servers.
Players earn Credits through gameplay and freely buy, sell, and trade any item — vanilla or modded — with true supply-and-demand pricing.

Built for ATM10-scale packs, persistent servers, and competitive economies.

🔹 Core Systems

💰 Credits Currency

• Server-authoritative virtual currency (Credits)
• Persistent balances across server restarts
• Real-time client sync (no client manipulation)
• Fully data-driven reward configs (JSON)
• Centralized wallet management

⚔️ Credit Earning Mechanics

🧟 Mob Kills

• Dynamic tiered rewards (T1–T8: 2 → 2000 Credits)
• Intelligent mob classification
• Player power scaling to prevent farming exploits
• Shared damage tracking for group kills
• Challenge ratio bonuses:
  • Under-geared players earn more
  • Over-geared players earn less

Anti-Exploit Protections

• ❌ No rewards from spawners
• ❌ No spawn-egg mobs
• ✔ Damage contribution tracking
• ✔ Spawn origin validation

⛏️ Ore Mining

• Rewards for valuable blocks (Coal → Ancient Debris)
• Configurable per-ore payouts
• Player-placed block detection
• No credit farming from placed ores

🛒 Marketplace System

📘 Order Book

• Separate buy & sell books per item
• Price-time priority matching
• Partial order fills
• Up to 20 active listings per player

🔐 Escrow System

• Credits escrowed for buy orders
• Items escrowed for sell orders
• Prevents duplication and rollback exploits
• Secure transaction validation

🔄 Auto-Stock Listings

• Automatically restock from inventory
• Up to 256 items per listing
• FIFO priority for multiple auto-stock orders
• Smart item identity matching (ignores NBT)
• Live quantity updates

📊 7-Day Sold Statistics

• Volume-weighted average price
• Historical sales tracking
• “Use Avg” quick-price button
• Market activity insights:
  • Seller count
  • Average price trends

🏷️ Player Stalls

• 8 customizable styles:
  • Default, Blue, Earth, Fire, Ice, Purple, Dark, Royal
• Persistent stall names
• Open / edit / close stalls
• Stall-based browsing & filtering
• Visual theming per stall

🤝 Trade Floor System

🧾 Trade Listings

• Direct player-to-player trading
• Custom names, descriptions, and icons
• 10-minute listing expiration
• Session-based trading flow

🔐 Trade Sessions

• Secure 2-player trading interface
• Item offer & acceptance system
• Optional coin-flip gambling mechanic
• Session rejoin ban (5 min)
• Leave cooldown (1 min)

🛡️ Trade Security

• One buyer per listing
• Session-locked inventories
• Atomic transaction commits
• Invariant validation checks

🖥️ User Interface

📂 Market Screen (6 Tabs)

🔍 Browse Market

• Search by item name
• Filter by stall owner
• Sort by price (low → high / high → low)
• Enchantment & modifier previews
• Multi-seller aggregation
• Quick-buy interface

➕ Create Order

• Deposit directly from inventory
• Price quick-actions (±10%)
• Max-quantity button
• 7-day average price suggestions
• Market activity indicators
• Withdraw unsold inventory

📦 My Orders

• View all active listings
• Auto-fill toggle per order
• Real-time quantity updates
• Bulk cancel identical orders
• Confirmation prompts

🤝 Trade

• Browse player trade listings
• Create new trade offers
• Join active trade sessions
• Session status indicators

🎁 Collect

• Collect sold items
• Collect earned credits
• Transaction history

🏪 Stalls

• Browse all player stalls
• Filter by stall style
• View stall inventories

🔁 Trade Session Screen

• Interactive offer UI
• Coin-flip animation widget
• Real-time updates
• Secure item transfers

💾 Data Persistence

SavedData Systems

• MarketData – Orders, stalls, listings
• CreditsManager – Player wallets
• PurchaseData – Inbox items & credits
• SoldStatsData – 7-day sales history
• PlacedBlockTracker – Ore anti-exploit
• MobSpawnTracker – Mob anti-exploit

🚫 Anti-Exploit Systems

• Spawner mob detection
• Spawn-egg tracking
• Player-placed block detection
• Power-scaled rewards
• Escrow enforcement
• Session-locked trades
• Cooldowns for rejoin & leave
• Transaction validation

✨ Quality-of-Life Features

• Rich item tooltips
• Text truncation handling
• Scroll indicators
• Hover highlights
• Confirmation dialogs
• Visual feedback & animations
• Tab persistence
• Smart caching (no flicker)
• Keyboard shortcuts (ESC to close)

🛠️ Developer Tools

• /market – Open marketplace UI
• /market purge – Clear all market data (OP only)
• Comprehensive logging
• Debug configs
• Trade invariant checker
• Timing guards

⭐ Why Use Swells Marketplace?

✔ Secure – Server-authoritative, escrow-based
✔ Scalable – Thousands of listings, persistent data
✔ Fair – Power-scaled rewards, shared damage logic
✔ Balanced – Market-driven pricing, anti-inflation systems
✔ Flexible – JSON configs, custom stalls, extensible design
✔ Reliable – Atomic transactions, crash recovery
✔ Polished UX – Clean UI, smart suggestions, rich feedback

👉 Join the Discord: https://discord.gg/U3kU8zhTNd