Environment Variables

Complete reference of all environment variables.

Server Variables

Variable	Default	Description
JAVA_XMS	4G	Minimum Java heap size
JAVA_XMX	8G	Maximum Java heap size
BIND_PORT	5520	Game server UDP port
AUTO_DOWNLOAD	true	Auto-download game files on startup
SERVER_EXTRA_ARGS	-	Additional arguments for the server
TZ	UTC	Container timezone

Panel Variables

Variable	Default	Description
PANEL_USER	admin	Login username
PANEL_PASS	admin	Login password
PANEL_PORT	3000	HTTP server port
JWT_SECRET	(random)	Secret key for JWT signing
MODTALE_API_KEY	-	API key for Modtale integration

Docker Variables

Variable	Default	Description
CONTAINER_NAME	hytale-server	Name of the game server container

Detailed Descriptions

JAVA_XMS / JAVA_XMX

Controls Java Virtual Machine memory allocation.

# Minimum 4GB, maximum 8GB
JAVA_XMS=4G
JAVA_XMX=8G

RAM Guidelines

Players	Recommended
1-10	4G
10-20	6G
20-50	8G
50+	12G+

AUTO_DOWNLOAD

When true, the server will automatically download HytaleServer.jar and Assets.zip from the official source on first startup.

# Disable for ARM64 or manual setup
AUTO_DOWNLOAD=false

ARM64

Auto-download is not available on ARM64 systems. Set to false and provide files manually.

SERVER_EXTRA_ARGS

Pass additional arguments to the Hytale server executable.

# Enable mods
SERVER_EXTRA_ARGS=--mods mods

# Multiple arguments
SERVER_EXTRA_ARGS=--mods mods --debug

TZ (Timezone)

Sets the container timezone for log timestamps.

TZ=America/New_York
TZ=Europe/London
TZ=Asia/Tokyo

Full timezone list

JWT_SECRET

Secret key used to sign JWT tokens. If not provided, a random key is generated on startup.

# Optional but recommended for persistent sessions
JWT_SECRET=your-very-long-random-string-here

INFO

If not set, a new random secret is generated each time the panel restarts, invalidating all existing sessions.

MODTALE_API_KEY

API key for Modtale mod repository integration.

MODTALE_API_KEY=your-modtale-api-key

When configured, enables:

• Mod browsing in the panel
• One-click mod installation
• Update checking

Example .env File

# ===================
# Server Configuration
# ===================
JAVA_XMS=4G
JAVA_XMX=8G
BIND_PORT=5520
AUTO_DOWNLOAD=true
SERVER_EXTRA_ARGS=--mods mods
TZ=America/New_York

# ===================
# Panel Configuration
# ===================
PANEL_USER=myadmin
PANEL_PASS=supersecurepassword123
PANEL_PORT=3000
JWT_SECRET=change-this-to-a-random-string

# ===================
# Optional Integrations
# ===================
MODTALE_API_KEY=your-api-key