Proton Drive CLI 0.9 for Windows: WinGet Setup, Scripted Transfers and Backup Limits

Timeline and current version​

Proton announced that the CLI was "here, available for Windows, macOS, and Linux." The launch post says it came about a week after Proton finished rolling out its Drive SDK. The AUR package for the Linux binary was first submitted on 2026-06-09, which fits a June launch.

The newest build is Proton Drive CLI 0.9.0, released on 2026-10-05. Proton's download listing includes macOS, Linux (glibc and musl) and FreeBSD builds with SHA-512 checksums. Windows builds are listed on the release page too. The WinGet package Proton.ProtonDrive.CLI is at version 0.9.0, so Windows users can install it with winget install -e --id Proton.ProtonDrive.CLI.

Third-party projects that wrap the CLI have looked at the 0.9.0 changes. One Home Assistant add-on maintainer reported that 0.9.0 only adds filesystem size and takeout run compared with 0.8.0. That is a community observation, not Proton release notes. It does suggest the update is a small one for existing scripts.

What the CLI does​

Proton says the CLI brings its cloud storage and end-to-end encryption to scripts, backups and deployment pipelines. It is built on the same SDK as the official apps and is fully interoperable with them. Files you touch from the terminal therefore appear in the same Drive account you see on the web, desktop or phone.

At launch, the CLI covered the essentials:

• Sign in and out.
• Browse and manage files and folders, including trash.
• Upload and download.
• Handle sharing and invitations.

Output is plain text by default. Add --json (or -j) for output that other tools can parse. You can run one-shot commands, or type proton-drive with no arguments for an interactive shell.

Getting started​

Proton's support page gives this basic flow:

1. Download the binary for your platform and open a terminal in that folder.
2. Run ./proton-drive auth login. A browser window handles authentication, so no password goes on the command line.
3. Run ./proton-drive filesystem list /my-files to see the root of your Drive.
4. Upload with a command like proton-drive filesystem upload ./reports/* /my-files/Reports --conflict-strategy skip. This is Proton's own example, and skip is one conflict option.
5. Download with proton-drive filesystem download /my-files/Reports ./backups.
6. Share with proton-drive sharing invite, specifying a user, a role and an optional message. Check who has access with proton-drive sharing status.

For the full list of options, run proton-drive help or proton-drive <command> --help. On macOS and Linux, run chmod +x proton-drive first. Then proton-drive version confirms which build you have.

Backup tool or file-transfer tool?​

The sponsored coverage leans heavily on the word "backup". Proton's own wording is narrower, and the difference matters.

Proton says the CLI complements the Drive app and is not a full replacement. In the launch post, only the apps include a full background sync engine. The CLI runs an operation, reports whether it worked, and exits. It suits tasks such as these, all drawn from Proton's own examples:

• Uploading files after a build.
• Taking a snapshot of a shared folder.
• Revoking access when someone leaves.

If you schedule an upload with Task Scheduler or cron, you still have to handle the rest yourself:

• Choosing what to copy.
• Detecting changes.
• Monitoring failures.
• Testing restores.

I found nothing in the documentation about retention policies or versioned recovery for the CLI itself. Treat it as an encrypted transport for your own backup logic, not a finished backup system.

One more point on scheduling. Proton's launch post mentions cron, and its business page lists cron, GitHub Actions, Ansible and deploy scripts. Windows readers can wrap the same commands in Task Scheduler or PowerShell. I did not find an official Task Scheduler guide, though.

Security and setup caveats​

Proton says everything done through the terminal gets the same end-to-end encryption as the rest of Drive. That is the vendor's claim. It does not protect you from a compromised machine. The login session still lives on your device.

• Credential storage. After login, the session is kept in the OS secret store. That is Windows Credential Manager, macOS Keychain, or libsecret on Linux. The README also lists a pass option. A plaintext file mode exists, but it is marked as testing-only and "do not use".
• Headless servers. Login needs a browser, and a secret store has to be available. That makes a bare headless box less trivial than the marketing suggests. An AUR packager noted that the Linux binary needs an org.freedesktop.secrets provider at runtime.
• Older NAS hardware. The README says that if the default Linux x64 build crashes with Illegal instruction, you should use the linux/x64-baseline build. This is common on NAS and embedded CPUs without AVX2.
• Local data locations. On Windows, cache, app data and logs sit under %LOCALAPPDATA%\proton-drive-cli. Setting PROTON_DRIVE_CACHE_DIR moves them all into one directory.
• Thumbnails. Uploads generate previews for common image types. Use --skip-thumbnails if your system doesn't support Bun's image API.

Rate limits and fair use​

Proton says the CLI follows the same fair-use policy as its other clients. It tells users to transfer only what has changed, and to avoid re-uploading the same files or rewriting whole folders. Accounts with unusually high traffic can be temporarily throttled. A naive nightly job that re-uploads everything is exactly what Proton is warning against. Build your scripts to skip unchanged files.

What's coming​

Proton listed these planned additions:

• Photos and albums.
• Public-link sharing.
• Multi-account support.

Those were plans as of the June announcement. I found no later confirmation of their status. Proton also said a full Linux desktop client with sync was in development. Its business page says the CLI is included in all Proton for Business plans.

Who should care​

Developers, admins and home-lab users who already script their workflows get a supported option in place of brittle reverse-engineered tools. Proton's launch post says that was the previous alternative to doing things by hand. If you only want folders kept in sync on a PC, the regular Drive app is still the right tool.

The sponsored article also points to legal, accounting and healthcare firms. Nothing in Proton's documentation shows the CLI meets any regulatory standard for those records. Check compliance requirements yourself before relying on it for them.