An optional download that lets Voltway control charging on your Mac.
You do not need this to use Voltway. The power-flow diagram, the battery forensics and the history all work without it. The helper only adds charge control.
It is a root background daemon, not a one-off password prompt. Once installed it runs as root, starts at every boot, stays resident, and listens on your Mac's loopback interface. The section below sets out exactly what gets installed and why it has to work that way — read it before you decide.
Limiting charge means writing to your Mac's System Management Controller — the chip that actually runs the charger. That requires administrator privileges, and Mac App Store apps are not permitted to request them (App Store Review Guideline 2.4.5(v)).
So rather than ask for privileges it is not allowed to have, Voltway keeps that work in a small, separate program that you install yourself and can remove at any time. The App Store app never escalates and never installs anything.
This helper is not part of the Mac App Store app and does not come from the App Store. It is a separate download from this page, signed with an Apple Developer ID certificate and notarized by Apple.
Three things, and it is worth knowing exactly what they are before you run the installer:
/usr/local/libexec/voltway/VoltwayChargeHelper — the helper itself, owned by root:wheel, mode 755./Library/LaunchDaemons/com.mwsupplylimited.voltway.chargehelper.plist — the launchd job that starts it./Library/Logs/Voltway/ — its log files. Your chosen limit is saved separately in /Library/Application Support/Voltway/policy.json.The launchd job is a system daemon marked RunAtLoad and KeepAlive. In plain terms: macOS starts the helper as root when your Mac boots, before anyone logs in, keeps it running whether or not Voltway is open, and restarts it if it ever exits. Installing it is not a one-time elevation that ends when the installer closes — it is a permanent, privileged background process, and it stays until you remove it.
The helper runs a small HTTP control server bound to 127.0.0.1 port 53845 — your Mac's own loopback interface, and nothing else. It is never bound to a network-facing address, so nothing outside your Mac can reach it. This is how a sandboxed App Store app, which has no privileges of its own, asks a privileged process to change a setting. The helper verifies the connecting app’s code signature before accepting policy changes. Status reads and restoring normal charging remain available without that authorization.
The charge limit lives in registers on your Mac's power controller, and those registers do not survive a power cycle. If the helper only ran while Voltway was open, your limit would quietly vanish every time you shut down, and would not come back until you next launched the app — which is exactly the failure people report with charge limiters that do not run at boot. Running at boot is what makes the limit mean anything. Running as root is what makes writing to the power controller possible at all: there is no unprivileged API for it, on any Mac.
This program can stop a Mac charging, so it is built to fail in the safe direction:
Some Macs do not expose a charge-control interface at all. Voltway detects this and tells you plainly rather than pretending the setting worked.
Download Voltway Charge Helper 1.2.1
161 KB · macOS 14 or later, Apple silicon
Open the downloaded .pkg and follow the installer. macOS will ask for your administrator password — that prompt comes from the system installer, not from Voltway, and it is what allows the helper to be installed as a root daemon.
Signed with a Developer ID certificate and notarized by Apple, so Gatekeeper will open it without warnings. If you want to confirm you got the same file we published, check its SHA-256 before opening it:
shasum -a 256 ~/Downloads/VoltwayChargeHelper.pkgIt should print:c1789e4eee3a30c66221d7f8a6d12836c2a8f5d554a9d7487f4c61a5bce2e897
Open the new package to upgrade. The installer restores normal charging first; after upgrading, reopen Voltway and re-enable your preferred limit.
Charge control requires Voltway Pro and supported firmware. The displayed percentage is an estimate, and macOS, sleep and safety recovery may allow charging above the selected level. This is a software charge policy, not a hardware guarantee. Version 1.2.1 was checked on an M5 Max MacBook Pro running macOS 26.6.2; other hardware and firmware may behave differently.
Run this in Terminal:
sudo voltway-helper-uninstallIt stops the daemon first, then restores normal charging and reads the setting back to confirm the charger really was released. Only once that check passes does it delete the helper, its launchd job, its log directory, your saved limit and the uninstaller itself. After it finishes, no Voltway process runs as root on your Mac and nothing of it is left behind — you do not need to clean up anything by hand.
If that read-back ever fails it deletes nothing. Removing the helper while the charger is still held would leave you unable to charge with nothing on the Mac able to release it, so instead it puts the helper back — it keeps retrying on its own — and asks you to run the command again. The fallback beyond that does not depend on our software at all: the charge-limit registers are cleared by a power cycle, so shutting down fully and starting up again returns the charger to normal.