s&box Dedicated Server - Pelican Egg

Pelican Egg and Docker image for the s&box Dedicated Server, running natively on Linux with .NET Runtime.

Status / Disclaimer

This egg is experimental. The s&box dedicated server on native Linux is not officially supported by Facepunch and may break with any game update. The initial startup may appear stuck — this is normal while assets are being downloaded. Monitor progress via the network graph in the panel.

Overview

• Docker Image: ghcr.io/freshdoktor/yolks:sbox
• Base: ghcr.io/parkervcp/yolks:ubuntu with .NET 10 Runtime and SteamCMD
• Steam App ID: 1892930
• Stop Signal: ^C (SIGINT)

Project Structure

.
├── egg-sbox.json                        # Pelican Egg definition
├── yolks/sbox/
│   ├── Dockerfile                       # Docker image (runtime)
│   ├── entrypoint.sh                    # Server startup script
│   └── build.sh                         # Local build script
├── scripts/
│   ├── install.sh                       # Readable copy of egg install script
│   └── entrypoint.sh                    # Readable copy of entrypoint script
└── .github/workflows/
    └── docker-publish.yml               # CI/CD: build + push to GHCR

The scripts/ directory contains readable copies of the scripts embedded in egg-sbox.json and yolks/sbox/entrypoint.sh for easier review. The actual scripts used are the ones in the egg JSON and the Docker image.

Install vs Runtime

• Install (egg-sbox.json script): Runs once in ghcr.io/parkervcp/installers:ubuntu as root. Downloads SteamCMD and s&box server files to /mnt/server.
• Runtime (yolks/sbox/): Custom image based on ghcr.io/parkervcp/yolks:ubuntu with .NET 10 Runtime and SteamCMD pre-installed. Runs the server via dotnet sbox-server.dll as non-root container user.

Variables

Variable	Default	Description
GAME	facepunch.sandbox	Game mode (e.g. facepunch.sandbox, thieves.terrortown)
SERVER_NAME	s&box Server	Server name in browser
MAP	(empty)	Map to load (empty = default)
MAX_PLAYERS	8	Maximum player count
SBOX_EXTRA_ARGS	(empty)	Additional startup arguments
SBOX_AUTO_UPDATE	1	Auto-update via SteamCMD on startup
ENABLE_DIRECT_CONNECT	0	Set to 1 to advertise direct connections and bypass Steam relay
SERVER_PORT	27015	UDP port — only used when ENABLE_DIRECT_CONNECT=1
QUERY_PORT	(empty)	Steam server browser query port, optional
TOKEN	(empty)	Steam Game Server Login Token, optional (hidden)
SBOX_BRANCH	(empty)	SteamCMD beta branch (hidden)

Building the Docker Image Locally

cd yolks/sbox
./build.sh
# or manually:
docker build -t ghcr.io/freshdoktor/yolks:sbox .

To build and push a beta image for testing on Wings without touching the production tag:

cd yolks/sbox
bash build.sh ghcr.io/freshdoktor/yolks:sbox-beta
docker push ghcr.io/freshdoktor/yolks:sbox-beta

In the Pelican panel, switch the server's Docker Image to sbox-beta under Startup to test it. Switch back to sbox once verified.

Testing

docker run -it \
  -e GAME=facepunch.sandbox \
  -e SERVER_NAME=Test \
  -e MAX_PLAYERS=8 \
  -e SERVER_PORT=27015 \
  -e SBOX_AUTO_UPDATE=1 \
  ghcr.io/freshdoktor/yolks:sbox

The server should start and output "Loading game" or "Server started".

Pelican Installation

1. Import egg-sbox.json in the Pelican Panel under Eggs.
2. Create a new server and select the egg.
3. The image ghcr.io/freshdoktor/yolks:sbox is used automatically.

CI/CD

The GitHub Actions workflow automatically builds and pushes the Docker image to ghcr.io/freshdoktor/yolks:sbox on:

• Push to main with changes to yolks/sbox/Dockerfile, yolks/sbox/entrypoint.sh, or the workflow itself
• Manual trigger via workflow_dispatch