DEV Community: umbra

I built a macOS security tool that locks your secrets when you walk away

umbra — Sun, 21 Jun 2026 14:05:38 +0000

CHIMERA is an open-source macOS security "organism" — one local process
orchestrating 8 native organs (C / C++ / ARM64 asm) that react to threats
together, entirely on your machine. No cloud, no telemetry, no account.

Flagship reflex: pair it to your phone over Bluetooth, walk away, and your
Mac locks itself (vault sealed, screen locked) on its own. Come back and it
stands down — but never auto-unlocks (BLE is spoofable, so "return = unlock"
would be a backdoor). Proximity is a key that only locks; coming back is
always your password.

It's early and honest: alpha, clone-and-build, self-signed (Apple Development
cert only, no notarized download yet). I'm posting now because you don't have
to trust me — everything it does is in the source, and every reflex it fires
lands in an audit trail you can read.

60-second verify: after build, python -m core status shows all 8 organs
live, 6 armed reflexes, and the audit log of every defensive action.

Repo (with a 30s demo): https://github.com/umbraaeternaa/macbastion

Happy to dig into the architecture — native organs under a Python brain over
a UNIX socket, the reflex/event model, why proximity only locks.

I built a macOS security tool that locks your secrets when you walk away

umbra — Sun, 21 Jun 2026 14:05:38 +0000

60-second verify: after build, python -m core status shows all 8 organs
live, 6 armed reflexes, and the audit log of every defensive action.

Repo (with a 30s demo): https://github.com/umbraaeternaa/macbastion

Happy to dig into the architecture — native organs under a Python brain over
a UNIX socket, the reflex/event model, why proximity only locks.