A small, simple, private, offline-first and native image flasher.
Freetracer is a small, fast, zero-tracking, open-source utility for securely writing common formats of bootable images (ISO/IMG/BIN, etc.) to removable media such as USB drives and SD cards. It’s built for people who value privacy by default: no ads, no telemetry, no surprise network calls — just a clean, friendly experience that stays out of your way. The signed bundle weighs in at roughly 5 MB and launches instantly on native macOS hardware.
| 🛡️ Privacy-first | 🔌 Works fully offline | ⚡ Native Zig speed |
|---|---|---|
| No telemetry, ads, or surprise permissions — just scoped access when you request it. | Zero network calls by default; optional version check you can disable entirely. | Small, written in Zig with 2 dependencies and little overhead. |
If you’ve ever wondered why a calculator wants your microphone, you’re not alone. In a world of habitual data collection and ad-tech, Freetracer is intentionally boring: it flashes images, stays offline, and doesn’t track you. That’s it.
- Create bootable USB and SD cards with a few clicks
- Supports ISO 9660, hybrid ISOs, and common image formats
- Handles large images (5GB+) without fuss
- Minimal, intuitive UI with tasteful pixel-art accents
- Offline-first design
- The only optional network call is a version check to
github.com - You can disable update checks entirely
- The only optional network call is a version check to
- Safety rails to help you avoid writing to internal/system disks
- Small, fast, and fully native (Zig + C/Obj-C) with minimal dependencies
- No ads, no trackers, no notifications, no spyware, no opaque network requests
- Limited permissions, only when you ask for them
- Free and open source forever!
It’s surprisingly common for simple utilities to request broad access or phone home. Freetracer doesn’t.
What Freetracer does not do:
- Does not include analytics SDKs, telemetry, or A/B testing
- Does not collect, sell, or share personal data
- Does not show ads or use embedded ad trackers
- Does not request microphone, camera, Bluetooth, or other unrelated permissions
What Freetracer does do:
- Scoped file access: When you pick or drag-and-drop an image, Freetracer requests access only to that item or folder (e.g.,
~/Downloads). By design, it will reject files selected from outside the logical user locations of~/Downloads,~/Documents, or~/Desktop. - Privileged operations isolated: On macOS, a small Privileged Helper Tool (Apple-endorsed pattern) performs tasks that require elevated privileges (e.g., unmounts, disk eject). The main app talks to it over XPC using a Mach service, keeping sensitive operations contained and auditable.
- Transparent permissions: The helper inherits only the permissions the app explicitly has. No silent escalation, no surprise access.
Transparency ledger (full details in Security & Privacy guidance):
| What we ask for | Why we need it | When it’s requested |
|---|---|---|
Downloads, Documents, Desktop folder access |
Access image files you explicitly choose | Only after you pick or drop a file |
| Privileged helper install (macOS) | Safely unmount and write removable media using macOS’ helper pattern | First time install and on version updates |
| Optional update check (GitHub) | Let you know when a new build is available | Only if you keep auto-checks enabled |
Privacy in practice: Freetracer rejects files outside common user folders by design, and privileged work happens inside a sandboxed helper process. Peek under the hood in the architecture overview.
- macOS 10.13 High Sierra and later
- Linux — work in progress (coming soon)
- Windows — not planned; we recommend Rufus
- Download the latest release for macOS (universal or Apple Silicon build).
- Drag to Applications.
- Launch Freetracer, select your image file and target drive, and flash.
On first use, macOS may prompt for access to files you choose — this is expected and limited to your selection.
Prerequisites
- Zig (matching the version in this repo’s build files)
- Xcode Command Line Tools (for SDKs and codesign)
- A valid Apple Developer ID certificate for signing the helper and app (recommended for local testing; required for distribution)
Build steps
Populate the property lists:
- For the main app, edit
./macos/Info.plistwith your Apple Developer Certificate ID, amend bundle ID in./src/env.zig - For the helper, edit
./macos-helper/src/env.zigwith your Apple Developer Certificate ID, similarly, amend the bundle IDs and test paths.
Note
If you're not using an organizational certificate and using a personal one, modify the [subject.OU] = XXXXXXXX fields to: [subject.CN] = FirstName LastName (Apple Development). Run codesign -d -r- "path/to/Freetracer.app" 2>/dev/null for codesign to generate the exact string to put in the plist key string.
Important
Codesigning is required for XPC communication and for launchd to register and launch the helper binary.
Build the library, helper, and main app:
zig build -Dtarget=aarch64-macos --release=safe bundleCodesign the helper and the app (replace IDs with your own):
codesign --force --sign "{Your Apple Developer Certificate ID}" \
-i "com.{your-id}.freetracer-helper" \
./Freetracer.app/Contents/Library/LaunchServices/com.{your-id}.freetracer-helper
codesign --force --sign "{Your Apple Developer Certificate ID}" \
-i "com.{your-id}.freetracer" \
--options=runtime \
./Freetracer.appTip
For Intel builds, adjust the -Dtarget accordingly (e.g., x86_64-macos).
We welcome contributions of all kinds — bug reports, docs, code, design, and testing.
- Please read
CONTRIBUTING.mdfor our workflow, coding guidelines, and tips for navigating the codebase. - You can help even without writing code — thoughtful issues and UX feedback are incredibly valuable.
- Star us on GitHub to show support
- Report bugs in the issue tracker
- Email us with ideas or questions [email protected]
- Follow Orbitixx on BlueSky, X (Twitter), and Instagram
Freetracer is licensed under the GNU General Public License v3.0 - see the LICENSE file for details.
Built with care — and without trackers.