Building a Minecraft Server in Rust What is mc-rust? mc-rust is a Minecraft server built entirely in Rust. Instead of using the official Java server, we wrote our own from scratch using Rust and the Valence game framework. Why Build Our Own Minecraft Server? 1. Learning: Understand how multiplayer games work at the protocol level 2. Performance: Rust is faster than Java for certain workloads 3. Custom Features: Add game mechanics that the official server doesn't have 4. Async: Handle thousands of players with async networking How Minecraft Servers Work Players connect and send data over network. The server must: - Handle network packets (client connects, moves, clicks, etc) - Update world state (blocks, entities, positions) - Send updates back to all connected players - Store chunks (16x16 blocks of terrain) - Manage inventory and player interaction Our Approach 1. Connection: Accept players joining the server (TCP connections) 2. Protocol: Understand Minecraft protocol (what packets mean) 3. Entity System: Track players, mobs, projectiles 4. Chunk Loading: Manage terrain rendering for players 5. Interaction: Handle block breaking/placing, crafting 6. Storage: Save player data and world state What We Support - Minecraft 1.20.1 protocol compatibility - Multiple players on same server - Breaking and placing blocks - Inventory management - Survival and Skyblock game modes - Custom game rules Performance: Why Rust? Rust features that help: - No garbage collection: Predictable latency - Async/await: Handle thousands of concurrent connections - Memory safety: No crashes from memory bugs - Speed: Comparable to C++ performance - Compile-time checks: Many bugs caught before running The Async Part Instead of one thread per player (slow), we use async: ```rust use tokio::net::{TcpListener, TcpStream}; async fn handle_client(socket: TcpStream) { // Handle this player } #[tokio::main] async fn main() { let listener = TcpListener::bind("0.0.0.0:25565").await.unwrap(); loop { let (socket, _) = listener.accept().await.unwrap(); tokio::spawn(handle_client(socket)); // Handle each player } } ``` This handles 1000s of players with minimal resources. Future Work - More game modes - Redstone (complex logic system) - Better world generation - PvP systems - Cross-server communication Current Status This is a private research project. Source code not public yet, but we're learning a lot about: - Network protocols - Game server architecture - Rust systems programming - High-performance networking Why This Matters Shows that you can build complex multiplayer systems in Rust. The server handles real-time game logic while supporting multiple players with async networking.