Server configuration

Environment variables for the Ceili chatserver.

Server configuration

The chatserver reads configuration from CHATSERVER_* environment variables. If a value is missing or invalid, the server uses the default shown below.

Variable	Default	Description
`CHATSERVER_HOST`	`0.0.0.0`	Address where the HTTP and WebSocket server listens.
`CHATSERVER_PORT`	`8081`	TCP port for health checks, voice bootstrap, and WebSocket connections.
`CHATSERVER_WS_READ_BUFFER`	`1024`	WebSocket read buffer size in bytes.
`CHATSERVER_WS_WRITE_BUFFER`	`1024`	WebSocket write buffer size in bytes.
`CHATSERVER_WS_MAX_MESSAGE_BYTES`	`4096`	Maximum accepted WebSocket message size.
`CHATSERVER_REPLAY_MESSAGE_LIMIT`	`50`	Number of recent room messages sent on connect or room switch.
`CHATSERVER_VOICE_LOOPBACK_SENDER`	`true`	Echoes direct voice signaling to the sender when enabled. Useful for diagnostics.
`CHATSERVER_VOICE_STUN_URLS`	`stun:stun.l.google.com:19302`	Comma-separated STUN URLs returned by `/voice/bootstrap`.
`CHATSERVER_VOICE_TURN_URL`	empty	Optional TURN server URL.
`CHATSERVER_VOICE_TURN_USERNAME`	empty	TURN username, used when a TURN URL is configured.
`CHATSERVER_VOICE_TURN_PASSWORD`	empty	TURN credential, used when a TURN URL is configured. Keep it secret.
`CHATSERVER_VOICE_EXTERNAL_IP`	empty	Public IP advertised by the voice service when the host is behind NAT.
`CHATSERVER_VOICE_UDP_PORT_MIN`	`0`	Minimum voice UDP port. `0` lets the runtime choose.
`CHATSERVER_VOICE_UDP_PORT_MAX`	`0`	Maximum voice UDP port. `0` lets the runtime choose.

Local development

A minimal local configuration can use the defaults:

CHATSERVER_HOST=0.0.0.0
CHATSERVER_PORT=8081

The default STUN server is enough for development networks that permit direct traversal. Verify the server with /healthz and /readyz before connecting the client.

Public deployments

For a public deployment:

terminate TLS at the reverse proxy and use wss:// from clients
configure a TURN server when users may be behind restrictive NATs
set CHATSERVER_VOICE_EXTERNAL_IP when the server’s public address differs from its local interface
set a bounded UDP port range and publish that range through the firewall or container
do not expose CHATSERVER_VOICE_TURN_PASSWORD in logs or public configuration examples

The configuration controls the current chatserver only. It does not configure the separate userserver scaffold.