Running (dev vs start)

start vs dev

• hstack start / hstack stack start <name>: production-like (prefer built UI; fewer watchers)
• hstack dev / hstack stack dev <name>: development (watch mode, faster iteration)

If you’re unsure, use hstack tui stack dev <stack> (or hstack stack dev <stack> in non-interactive environments).

TUI mode (recommended for interactive development)

For local interactive work, prefer wrapping your run command in the hstack TUI:

hstack tui stack dev dev
# mobile dev-client + QR:
hstack tui stack dev dev --mobile

In non-interactive terminals / CI (or if the TUI is unavailable), run the underlying command directly:

hstack stack dev dev

Browser origin isolation (important)

When you run multiple stacks, browser state (cookies/localStorage) can collide if you always use http://localhost:....

hstack prefers stack-specific origins for non-main stacks when it matters (so stacks don’t fight over browser auth/session state).

Tip: if you see “auth looks wrong” between stacks, check:

• which stack you’re using (hstack stack info <name>)
• which UI URL you opened (use the one printed by hstack)

Browser auto-open (--no-browser)

In interactive runs, hstack dev / hstack start may auto-open the UI in your browser.

• Disable: --no-browser
• Global disable: HAPPIER_STACK_NO_BROWSER=1

Watch mode (hot-reload-ish)

In interactive TTY runs, hstack dev enables watch mode by default:

• happier-cli changes → rebuild + restart the daemon
• some long-lived processes can be restarted safely when hstack knows they are stack-owned

Control flags:

• Force enable: hstack dev --watch
• Disable: hstack dev --no-watch

If hstack prints that a restart is disabled because the PID is unknown, re-run with --restart so hstack can spawn and track the process.

Safe restarts

Both hstack start and hstack dev support --restart:

hstack dev --restart
hstack start --restart

For a named stack:

hstack stack dev exp1 -- --restart
hstack stack start exp1 -- --restart

Stopping stacks safely

Stop a single stack:

hstack stack stop exp1

Stop multiple stacks:

hstack stop --except-stacks=main --yes

Useful flags:

• --aggressive: stop additional daemon-tracked sessions (still stack-owned)
• --sweep-owned: final sweep for processes that still carry the stack env in their process env
• --no-docker: skip Docker-managed infra shutdown

CLI build behavior (happier-cli)

When running stacks, hstack may ensure the CLI is built when needed (so the daemon can start).

Controls:

• HAPPIER_STACK_CLI_BUILD_MODE=auto|always|never
• HAPPIER_STACK_CLI_BUILD=0 (hard-disable)