Environment Variables

All configurable environment variables live in compose.yaml under the dev service. The init script writes them into /config on every boot, so they take effect immediately.

ANTHROPIC_AUTH_TOKEN is the only value you must provide: without it, Claude Code won't start. Every other variable falls back to the default shown in its table.

How it works

compose.yaml          init.sh              /config/.bashrc
(dev service)     →   writes vars  →      /config/.zshrc

Edit compose.yaml, recreate the container, done.

Claude Code / API

Env var	Default	What it does
ANTHROPIC_BASE_URL	(empty)	Leave empty for Anthropic. Set to a third-party URL (DeepSeek, OpenRouter, etc.) to use a different provider
ANTHROPIC_AUTH_TOKEN	(required)	Your API key. Get one at console.anthropic.com
ANTHROPIC_MODEL	claude-opus-4-8	Default model Claude Code uses for all tasks
ANTHROPIC_DEFAULT_OPUS_MODEL	claude-opus-4-8	Model used when Opus tier is selected
ANTHROPIC_DEFAULT_SONNET_MODEL	claude-sonnet-4-6	Model used when Sonnet tier is selected
ANTHROPIC_DEFAULT_HAIKU_MODEL	claude-haiku-4-5	Model for Haiku tier (lighter tasks, subagents)
CLAUDE_CODE_SUBAGENT_MODEL	claude-haiku-4-5	Model for background agents spawned by Claude Code
CLAUDE_CODE_EFFORT_LEVEL	max	Reasoning depth: low, medium, high, or max

Using a different provider

If ANTHROPIC_BASE_URL is left empty, Claude Code connects directly to Anthropic's API. To use a third-party provider, set the URL and adjust model names.

DeepSeek example:

ANTHROPIC_BASE_URL: https://api.deepseek.com/anthropic
ANTHROPIC_AUTH_TOKEN: sk-...       # your DeepSeek key
ANTHROPIC_MODEL: deepseek-v4-pro[1m]
ANTHROPIC_DEFAULT_HAIKU_MODEL: deepseek-v4-flash
CLAUDE_CODE_SUBAGENT_MODEL: deepseek-v4-flash

OpenRouter example:

ANTHROPIC_BASE_URL: https://openrouter.ai/api/anthropic
ANTHROPIC_AUTH_TOKEN: sk-or-v1-... # your OpenRouter key
ANTHROPIC_MODEL: anthropic/claude-opus-4-8

How to apply changes

Edit compose.yaml, recreate the container:

docker compose up -d --force-recreate

Or, for a quick test without recreating:

nano ~/.zshrc
source ~/.zshrc

Git / GitHub

Env var	What it does
GIT_USER_NAME	Your name for commits (git config user.name)
GIT_USER_EMAIL	Your email for commits (git config user.email)
GITHUB_TOKEN	GitHub fine-grained PAT, used for all git clone / push / pull

Creating a GitHub token

Go to github.com/settings/tokens?type=beta:

1. Repository access: "Only select repositories", pick which ones
2. Permissions: Contents (read/write as needed), Metadata (read, auto-selected)
3. Copy the github_pat_... token into GITHUB_TOKEN

The token can be revoked or scoped anytime. No account password stored: if the container is compromised, you only lose access to the repos you explicitly granted.

After setting these and recreating the container, git clone, git push, and git pull all use the token automatically.

Container settings

Env var	Default	What it does
CUSTOM_USER	abc	Custom username. Replaces the default abc user on boot
PASSWORD	(required)	Login password for the ttyd web terminal
SUDO_PASSWORD	(required)	Sudo password inside the container. Also used for SSH login
PUID	1000	User ID for file permissions
PGID	1000	Group ID for file permissions
TZ	Europe/Rome	Timezone

Session behavior

These variables are not set in compose.yaml. They are passed at connection time (by your SSH client or in the shell) to control what happens when you log in.

Env var	Default	What it does
NO_CLAUDE	(unset)	Set to 1 to skip Claude auto-launch and get a plain shell
TMUX_AUTO	(unset)	Set to 1 to auto-attach a persistent tmux session on login
TMUX_TIMEOUT	(unset)	Hours before a detached tmux session is auto-killed (-1 = never, 0 = on detach, N = after N hours)

Claude auto-launch

Claude launches automatically on every login (both SSH and web terminal). You land in /workplace with Claude ready. Exiting Claude (/exit or Ctrl+D) returns you to a normal shell prompt.

To skip the auto-launch:

NO_CLAUDE=1 ssh abc@<server> -p 2222    # → plain shell, no Claude

Persistent sessions with tmux

Set TMUX_AUTO=1 on your SSH client (e.g. Termius environment variables) to wrap every session in tmux. When you disconnect, tmux keeps running. When you reconnect, you reattach to the same session with Claude still there.

# In Termius: set TMUX_AUTO=1 in the host's environment variables
# In a terminal:
TMUX_AUTO=1 ssh abc@<server> -p 2222    # → auto-attached to tmux "main"

Use TMUX_TIMEOUT to auto-clean detached sessions. For example, TMUX_TIMEOUT=2 kills sessions that have been detached for more than 2 hours. Run tmux-keep inside a session to override this and keep it alive indefinitely.

See Daily Workflow for full tmux usage.