What is CommandBlock?

CommandBlock is a self-hosted manager for Minecraft (Java) servers. Pick a loader, click Create, and you get a running server in an isolated container - reachable by its own hostname through a single public port.

• Create in one click. Vanilla, Paper, Purpur, Fabric, Quilt, Forge, NeoForge or Spigot, on any Minecraft version that ships a server jar.
• One port, many servers. Every server is reached on 25565. The built-in router reads the address from the Minecraft handshake and forwards to the matching server - so smp.example.com and modded.example.com share one open port.
• Backups & cloning. World or full-server snapshots to an S3 bucket such as SeaweedFS - restore in place, schedule them with cron, or spin up a brand-new server from a backup.
• Wake on join, sleep when idle. Stop a server once it sits idle, and start it again the moment someone tries to join - holding the player until it's ready so they don't have to reconnect. Works on every version and every mod loader.
• Any client version. Optionally install the Via stack so clients from 1.8 up to current can join the same server, without touching authentication.
• Edit from the UI. A per-server settings modal: server.properties with a live MOTD editor, Java/memory runtime, the Minecraft version, a custom icon, and rename.
• Lifecycle controls. Start, stop, restart and delete from the UI, with live vitals per server - CPU, memory, uptime and players - and sleeping servers told apart from crashed ones.
• Bring your own auth. OIDC with any provider (Pocket ID, Authentik, Auth0…), or the bundled mock server for local development.

Architecture

Each server is provisioned as an isolated sibling container (itzg/minecraft-server) on the Docker host - not a child of CommandBlock - which is why CommandBlock mounts the Docker socket. Provisioned servers join CommandBlock's Docker network and publish no host port of their own; only the router's port is exposed.

Player --TCP 25565--> Router (in CommandBlock) --> mc-container (by hostname)

The control plane is the whole app: the Angular UI, the ASP.NET Core API, its Postgres metadata database, and the router.

Get started

• Self-hosting - run the image with docker compose.
• Servers - create and manage servers.
• Wake & sleep - idle servers that start themselves when someone joins.
• Hostname routing - how one port serves many servers.
• Developer setup - local dev with dotnet run + Bun.