Cairn Notes

Download Cairn 1.4.0

Released 8 October 2026. Release notes · This release on GitHub

Linux

For x86_64. The .deb and .rpm packages use the system's WebKitGTK 4.1 and GTK 3. The AppImage needs no installation.

Install the .deb on Debian or Ubuntu, or the .rpm on Fedora:

sudo apt install ./Cairn_1.4.0_amd64.deb
sudo dnf install ./Cairn-1.4.0-1.x86_64.rpm

Or make the AppImage executable and start it:

chmod +x Cairn_1.4.0_amd64.AppImage && ./Cairn_1.4.0_amd64.AppImage

Windows

For Windows 10 and 11 on x86_64. The installer installs Cairn for your user account, without administrator rights. If the WebView2 Runtime is missing, it downloads it from Microsoft.

The installer is not signed, so Windows SmartScreen says "Windows protected your PC" when you run it: choose More info, then Run anyway. On a Windows 11 PC where Smart App Control is on, there is no Run anyway, and Windows can block the installer and Cairn outright. Windows in the manual has more.

Android

For Android 7.0 or later, on arm64, armv7, x86 and x86_64. Open the APK on your phone and allow the install when Android asks: from Android 8, you let your browser or file manager install apps; on Android 7, you turn on Unknown sources in Android settings, then Security.

Every version is signed with the same key, so a new APK installs over an older one as an update and keeps your notebooks and your sync setup. The signing certificate's SHA-256 fingerprint is:

1D:10:FE:DC:B9:A2:55:63:DA:A0:59:AD:79:30:64:15:3D:A8:7F:92:C4:0C:49:A8:98:F2:00:AF:09:B9:82:8C

To check it, run apksigner verify --print-certs cairn-1.4.0-universal.apk (apksigner comes with the Android SDK build tools). It prints the same value in lowercase, without the colons.

Sync server

Only needed for sync. The image is for x86_64 machines with Docker. On another machine, such as a Raspberry Pi, build the image yourself, as Run a server in the manual describes.

Load the image, which is then called cairn-server:1.4.0:

docker load -i cairn-server-1.4.0-docker-image.tar.gz

Check your download

SHA256SUMS lists the SHA-256 of every file above.

On Linux, put it in the folder with your download and run:

sha256sum -c --ignore-missing SHA256SUMS

On Windows, open PowerShell in the folder with your download and run Get-FileHash Cairn_1.4.0_x64-setup.exe. Compare the hash it prints with the installer's SHA-256 under Windows, above. PowerShell prints it in capitals.

Other systems and versions

There is no macOS build, and Cairn has not been built or tested on macOS. There is no iOS app. Building from source describes how to build Cairn yourself. Older versions are on the releases page.