Installation
How to install COSY on your server.
COSY can be deployed using Docker Compose or Kubernetes. Both methods use the same interactive install script — just run it and follow the prompts.
HTTPS / TLS Support
COSY has built-in HTTPS support powered by automatic Let's Encrypt certificates. During installation, the script will ask whether you want to enable TLS. When enabled:
- Docker — COSY uses Caddy as its reverse proxy, which automatically obtains and renews TLS certificates. Ports 80 and 443 must be available.
- Kubernetes — COSY uses cert-manager with a Let's Encrypt ClusterIssuer. The installer can install cert-manager for you if it's not already present.
You'll need a domain name pointing to your server and an email address for Let's Encrypt notifications. TLS mode cannot be combined with a custom port — it always uses the standard HTTPS port (443).
Need a domain? Get a free subdomain at the Cosy Domain Provider — claim a
*.cosy-hosting.netsubdomain and point it to your server's IP address in seconds.
Quick Start
Download and run the install script:
sudo bash -c "$(curl -fsSL https://raw.githubusercontent.com/Magenta-Mause/Cosy/v1.0.3/install_cosy.sh)" _The script walks you through the setup interactively — it asks for the deployment method, admin username, domain, port, and optional footer information. Every prompt has a sensible default, so you can press Enter through the whole thing for a quick setup.
Docker vs Kubernetes
| Docker Compose | Kubernetes | |
|---|---|---|
| Best for | Single server, simple setups | Users who already have a cluster and already host multiple services on their server |
| Complexity | Low — single command, systemd autostart | Medium — requires existing cluster and Ingress controller |
| Scaling | Single instance | Single instance (game servers run on the backend pod's host) |
| Management | systemctl start/stop cosy | kubectl / ArgoCD |
| Storage | Game server volumes on disk | Game server volumes on disk (on the backend pod's host) |
Choose Docker if you have a dedicated server and want the simplest path to running COSY. Choose Kubernetes if you already run a cluster and want COSY deployed alongside your other workloads.
Docker Installation
Step-by-step walkthrough of the Docker setup.
Kubernetes Installation
Step-by-step walkthrough of the Kubernetes setup.
Uninstallation
How to completely remove COSY.
Security Notice
COSY requires access to the Docker socket (/var/run/docker.sock) to manage game server containers. This grants root-equivalent privileges on the host. Only deploy COSY in trusted environments and restrict network access accordingly.