Last year, we shared that we were rethinking how Proton Drive apps interact with our backend by building a shared, robust foundation that all clients can use. Our goal is to give everyone a faster and more reliable experience on Proton Drive, whether you’re using it on Windows, macOS, Android, iOS, or through the web app.

Today, we’re excited to give you a progress update, as the Proton Drive SDK has continued to mature behind the scenes and is now powering core file operations across all Drive apps.

Here’s what we’ve done so far and what’s coming next.

One SDK foundation for all Drive apps

The Proton Drive SDK is the shared layer that all Drive apps use to handle operations securely and efficiently. Instead of each app implementing this logic separately, they all rely on the same foundation.

The following are now available for preview:

• JavaScript SDK
• C# SDK
• Bindings for Swift and Kotlin

The JavaScript and C# SDKs are already powering some features in all Proton Drive clients. Starting next week, we’ll automate updates to the public repository(new window) so the SDKs will be updated more frequently as we continue to develop them.

File transfers are faster, more reliable

Developing the SDK has also given us the opportunity to rethink and optimize a lot of Drive’s most performance-intensive code, which we have now streamlined. As a result, Proton Drive apps now feature up to 60% faster uploads on iOS and 30% faster uploads and 70% faster downloads on web.

Beyond raw speed, the SDK is built to be our most robust and resilient implementation ever, especially under challenging network conditions.

What the SDK supports right now

Currently, the SDKs provide core Proton Drive functionality:

• Upload and download files
• Create folders
• Rename and move items
• Delete, restore, and permanently delete files

Authentication and other Proton-specific modules required for standalone third-party integrations are not yet supported. Those pieces will come later. For now, the Proton Drive SDK is best suited for contributors and early experimentation. It is not yet officially supported for use by third parties who want to integrate Proton Drive into their own products.

CLI tools coming soon

The SDKs don’t cover every workflow yet, especially with some features still in development. To fill that gap, we’re working on command-line interface (CLI) tools that provide Drive functionality not yet available in the SDKs. You will be able to:

• Run commands directly for common tasks
• Build on top of them without reverse‑engineering Proton Drive

We’re aiming to make these CLI tools available in the next quarter (April – June 2026).

What’s next

Over the course of 2026, we’ll migrate all existing Proton Drive features to the SDK, and build all new features on top of it.

Our priorities are to:

• Complete the SDK rollout across all Proton Drive clients, so the desktop, mobile, and web apps use the same codebase.
• Upgrade Drive’s encryption algorithms to use on‑device hardware acceleration, delivering faster operations while reducing CPU usage.
• Add the still-missing Drive features to the SDK, starting with Photos uploads and downloads, file sharing, devices, and file revisions.
• Gradually move toward a single, well‑documented integration path that third‑party apps can rely on.
• Build a Linux client using the SDK, which speeds up development and keeps it consistent with the other Proton Drive clients.

Want to help?

While the SDK isn’t ready yet for building fully standalone apps, we welcome feedback from contributors and early explorers. Take a look on the public repository(new window) and join the discussion on r/ProtonDrive(new window) using the sdk-preview-discussion tag.

Thank you for your continued support,

The Proton Drive engineering team