OrderX

A production-ready Paper 1.21.x marketplace plugin that implements a player-driven buy/sell order system with automatic order matching, escrow-based transaction safety, Vault economy integration, SQLite/MySQL persistence, and a full Bukkit inventory GUI.

Orders are matched automatically and continuously. Nobody trades directly with another player: money and items are held in escrow until an order fills, guaranteeing there is no item or money duplication even under concurrent access.

Features

• Buy and sell orders with configurable durations (up to 30 days, plus "permanent")
• Automatic order matching - buy orders fill against the cheapest sell, sell orders against the highest buy; oldest orders match first on ties; partial fills supported
• Escrow accounting - money and items are held in escrow until an order fills
• Strict serialization - every order mutation runs on a single-threaded order engine (double-fills are impossible)
• Fees - configurable buy/listing fee (at creation) and sell tax (at fill)
• Vault economy integration (required) and PlaceholderAPI support
• SQLite (default, WAL mode) and MySQL storage via HikariCP
• Full GUI - main menu, item picker, create-order wizard, my-orders, history, and market-info views, plus chat-based item search
• Expiry sweeper - expired orders auto-cancel and refund
• Admin tools - purge, statistics, force-cancel, config reload

Requirements

• Paper (or fork) 1.21.x, Java 21+
• Vault + an economy plugin (EssentialsX, CMI, CoinsEngine, etc.) - required
• PlaceholderAPI (optional)

Installation

1. Copy OrderX.jar into your server's plugins/ folder.
2. Make sure Vault and an economy plugin are installed.
3. Restart the server. Run /order to open the market.

Commands: /order buy|sell <item> <qty> <price>, /order myorders, /order history, /order market <item>, /order search <query>, /orderadmin for admins. Full docs shipped with the plugin (see README).