Fast mode (daemon)

cs --setup writes cs render + refreshInterval: 1 by default. A long-lived cs daemon pre-renders into ~/.cache/claude-statusbar/rendered.ansi; the statusLine command (cs render) is a thin reader that just cats the file. Each tick is ~3-5ms, so total CPU stays under 1% continuously. The legacy inline path (~30ms/tick, ~3% CPU at 1Hz) is still available via cs --setup --inline.

cs --setup               # default: daemon mode, auto-starts the daemon
cs --setup --inline      # opt out, use legacy inline path
cs daemon status         # check the daemon is alive
cs daemon stop           # stop the daemon (statusLine falls back to inline)
cs daemon start          # start it again

Crash safety: if the daemon dies or freezes, cs render notices rendered.meta.json is older than 5s and falls back to inline render — and lazily re-spawns the daemon in the background. You never see a frozen status line.

Optional: auto-start on login (launchd / systemd)

Lazy-spawn (above) covers most cases — the daemon comes up on first cs render. If you want stronger guarantees (auto-start at login, OS restarts the daemon on crash, survives reboots without cs render needing to fire first):

cs daemon install        # installs ~/Library/LaunchAgents (macOS) or
                          # ~/.config/systemd/user (Linux), starts the daemon
cs daemon service        # report whether the OS-level service is registered
cs daemon uninstall      # remove the LaunchAgent / systemd unit

On macOS, the LaunchAgent has KeepAlive=true and ThrottleInterval=10 — kill the daemon and launchd respawns it within 10 seconds. On Linux, the systemd user unit uses Restart=always (you may need loginctl enable-linger $USER for the daemon to survive logout).