Dark Bio - Ark Emulator

An emulated Ark enclave for development and demos. It boots the real ArkOS firmware inside QEMU, with an optional native window showing the device's physical face (4 RGB LEDs and a reset pin).

Caution

The emulator is not a vault. The backing disk image is an unencrypted qcow2 file on your host filesystem. Anything the emulated Ark stores ends up there, readable by anyone with access to your machine. Do not put real genomic data, real keys, or anything else you want to keep private into the emulator. It exists for development, demos, and integration testing only. The cryptographic and physical-security properties Dark Bio promises apply to the actual Ark hardware, not this emulator. For any workload where data confidentiality matters, use a real Ark.

Install

Download a build for your operating system and processor from GitHub Releases. Releases include QEMU and ArkOS, so you can launch the app without configuring either.

Platform	Installer	Portable version
macOS	.dmg	Unzip the .zip and open the app
Windows	.exe	Unzip the .zip and run ark-emulator.exe
Linux	.deb	Make the .AppImage executable and run it

On macOS, you can also install with Homebrew:

brew install --cask dark-bio/tap/ark-emulator

macOS requires version 15 (Sequoia) or later. Windows builds are unsigned; if SmartScreen blocks a downloaded release, choose More info, then Run anyway.

Get started

1. Open Ark Emulator.
2. In the settings screen, use New beside the filename to create an emulator file, or Open to choose one you already have.
3. Choose Save and start to remember your choices and boot the emulator. Use Start to boot without saving your settings.
4. Open Ark Hub in Chrome or Edge and connect to the running emulator.

Each .ark file stores one emulator's data. Open the same file to continue where you left off, or create a new file to start with a blank device.

Click the notch below the device to see its information, then the gear to open settings. Autostart starts your saved emulator automatically on the next launch. The developers section contains memory and environment settings. Settings saved while an emulator is running apply on a later launch; an environment change applies only to a newly created device.

To close the window, use your operating system's close or quit shortcut, such as Alt+F4 on Windows or Cmd+Q on macOS.

Run multiple emulators

Launch the app again to open another window. On macOS, use New Window (Cmd+N) in the app menu. Each running instance needs a different emulator file; use Open or New in that window to choose one.

Command line

Use ark-emulator to manage emulators without opening a window. Installing with Homebrew, the Windows installer or the .deb makes the command available in your terminal. On Windows, open a new PowerShell or Command Prompt window after installing.

ark-emulator start --headless  # boot without a window, return when ready
ark-emulator list              # show what is running on this computer
ark-emulator button press      # hold its reset button
ark-emulator button release    # release the CLI hold
ark-emulator stop              # shut it down

Omit --headless to show the device window. For a foreground process, use ark-emulator --headless --image demo.ark; Ctrl-C stops it. See ark-emulator help start for readiness, timeouts and image defaults. Button commands accept a locator, name, serial or image when several emulators are running. ark-emulator button press --release-after 3 schedules release after 3 s, even after the command exits. Use --release-after 0 to release immediately after pressing. See ark-emulator button press --help for delivery and hold behavior.

For the portable Windows ZIP, run .\bin\ark-emulator.cmd instead of ark-emulator from the extracted folder. On macOS and Linux, run the executable inside the portable build directly.

Hand the locator to ark, which talks to an emulated Ark exactly as it talks to hardware:

ark -d emulator:18181 status

A fresh emulator has a self-signed identity. ark enroll prints the Ark Hub address that gives it an attested one, valid for 30 days; after that, ark-emulator stop, wipe and start give a fresh device to enroll again.

ark-emulator --help lists every command and option, and ark-emulator help names the reference topics, whose sources in launcher/src/cli/help read the same on GitHub. AI agents should read ark-emulator help agents first, then ark help agents before driving the Ark itself. Apps to run on an emulator, in Rust, Go, C and Python, are at examples. Pairing and unlocking happen in Ark Companion, on iOS or Android.

Build from source

Install Rust, the Tauri system prerequisites, and QEMU, including qemu-img. Download a matching kernel and initramfs pair for your processor (arm64 or amd64) from the emulator firmware releases. Source builds do not bundle QEMU or firmware.

From this repository, run:

cargo build --release -p launcher
./target/release/ark-emulator \
  --kernel /path/to/kernel \
  --initrd /path/to/initrd.gz

For everything the executable can do, run ./target/release/ark-emulator --help.

Layout

path	role
launcher/	Rust runtime and optional Tauri window. Owns QEMU, the hardware connection and discovery, and carries the packaging config and macOS entitlements.
ui/	Static HTML/CSS/JS. Renders device state from Rust and forwards user interactions through Tauri commands.
docs/	Maintainer documentation. Currently the one-time Apple Developer setup the macOS signing in CI depends on.
.github/	CI. Builds an installer per platform, then smoke tests each no-install artifact on a clean machine. The scripts under scripts/ gather a relocatable QEMU and the pinned firmware for packaging; they are used by CI and runnable by hand. packaging/ holds the Homebrew cask template a release publishes to the tap.