Environment Variables

Environment Variables

Every environment variable a9s honors. Command-line flags always win over environment variables when both are set.

a9s-specific

Variable	Effect
A9S_MODE	A9S_MODE=web starts the HTTP server instead of the TUI — same as --web.
A9S_LOG_FILE	Path for diagnostic logs (off by default). --log-file wins when both are set.
A9S_CONFIG_FOLDER	Overrides the ~/.a9s root for config, themes, views, and the on-disk cache.
BROWSER	Opener command for the o (open in AWS console) key. The value is whitespace-split into a command plus arguments, so flags work — BROWSER="firefox --new-tab" — but it is never passed through a shell, so quoting is not interpreted. Unset, the platform default opener is used: open (macOS), xdg-open (Linux), rundll32 (Windows). In demo mode o shows a notice instead of opening; O always copies the URL.

Standards a9s follows

Variable	Effect
NO_COLOR	Set to any value to force monochrome output, regardless of theme. Follows the no-color.org standard. Useful for accessibility, scripting, or piping.

AWS standard variables

Variable	Effect
AWS_REGION	Region fallback when no region comes from -r, config, or the profile.
AWS_DEFAULT_REGION	Same as AWS_REGION, consulted after it.
AWS_PROFILE	Honored by the AWS SDK when no profile is set via -p or a9s config.
AWS_CONFIG_FILE	Alternate AWS config file for profile discovery (default ~/.aws/config).

Credentials resolve through the standard AWS SDK chain (AWS_ACCESS_KEY_ID, AWS_SECRET_ACCESS_KEY, AWS_SESSION_TOKEN, SSO sessions, instance roles, …) exactly as they do for the AWS CLI — a9s adds nothing on top.