Session protection for professionals who can't afford downtime. One click to prevent sleep, monitor your Mac's vitals, and guard long-running work — no Terminal required.
You can — SENTINEL wraps caffeinate under the hood. But SENTINEL gives you a visual dashboard, live system monitoring, timed sessions, reminders, connected service health checks, and one-click control. No memorizing flags, no forgetting to stop it, no Terminal babysitting.
No. Zero telemetry, zero analytics, zero network calls. The HTTP server runs on 127.0.0.1 (localhost only) — it's physically impossible for external machines to connect. Your data stays on your Mac.
Free gives you full session protection, system monitoring, timed sessions, away mode, Quick Protect preset, 2 connected services, auto-start on login, and macOS notifications. Pro unlocks Time Guardian reminders, 4 additional session presets, custom presets, macOS menu bar quick-toggle, unlimited connected services, and auto-protect rules. Core protection is always free — no artificial limits on the thing you need most.
SENTINEL uses Ed25519 cryptographic signatures — the same algorithm used by SSH, Signal, and WireGuard. License keys are verified offline using a public key embedded in the app. No server calls, no DRM, no internet required to activate.
Yes. SENTINEL runs on Python 3.10+ which supports both architectures natively. Tested on M1, M2, M3, M4, and Intel x86_64. Requires macOS 13 (Ventura) or later.
Time Guardian is a reminder system that nudges you after a set duration — without stopping your protected session. Set a 2-hour reminder, and SENTINEL sends a macOS notification when time's up. Snooze for 30 more minutes or dismiss. Your session keeps running. Perfect for anyone who loses track of time during deep work.
Your Mac never sleeps on the job.
Download SENTINEL free. Protect your first session in under 30 seconds.