built-in
28%
A tiny macOS service
Your external display,
finally in sync.
When macOS dims your MacBook — manually or via the ambient sensor — ddc-mirror applies the same brightness to each external monitor, using hardware control when it can and a color-profile-aware fallback when it can't. No menu bar. No hotkeys. No telemetry. Just brightness.
brew install emin93/tap/ddc-mirror
external
28%
How it works
-
01
Watches built-in brightness
Reads the same
DisplayServicessignal macOS uses for its own brightness HUD — including the ambient-light adjustments you don't think about. -
02
Picks the best display path
Uses Apple's native brightness API when available, DDC/CI for direct monitors, and profile-aware software dimming when docks or hubs block DDC.
-
03
Runs as a brew service
Installed once, started with
brew services. Survives reboots. Costs about twelve megabytes of memory and nothing else.
What it deliberately doesn't do
- No menu bar app. No preferences pane. No settings window. The only UI is the one Apple already shipped.
- No hotkey hijacking. Your brightness keys stay native. ddc-mirror only follows where macOS leads.
- No telemetry. No analytics, no update pings, no crash reporting. It can't tell anyone you installed it.
- No pro tier. MIT, free, forever. There is no paid version because there is no version to upgrade to.
Quickstart
# install & run as a service
brew install emin93/tap/ddc-mirror
brew services start ddc-mirror
# or run directly
ddc-mirrorThe eventual command is brew install ddc-mirror once it lands in homebrew-core. Until then, the personal tap above is the working incantation.