Switch to Open Source Without Starting Over

We started Foundation because we believe an open, decentralized Internet must be built on a foundation of open source hardware and software.

But people have spent years building their wallet setups. Asking them to move every asset and relearn everything is a real barrier. Legacy Mode lets them keep what they've built and put it on an open source foundation.

Today, we're releasing the beta of Legacy Mode for Passport Prime, enabling Ledger users to switch to open source hardware and software while keeping their existing accounts for supported assets. Legacy Mode runs open source cryptocurrency apps originally developed for Ledger and connects to familiar software wallets over USB.

The release accompanies our Switch campaign, built around a simple promise: switch to open source without starting over. As Ledger phases out support for the original Nano S, users can switch to Passport without transferring supported assets to new accounts. Their addresses, balances, and transaction history stay the same.

How Legacy Mode works

Ledger and its developer community have built an extensive library of open source cryptocurrency apps. Those apps normally run on Ledger's operating system, which includes proprietary code. Our compatibility layer allows supported apps to run on KeyOS, the fully open source operating system powering Passport.

To make this possible, we reimplemented the interfaces that Ledger's open source apps use to talk to BOLOS, its operating system. That includes cryptographic operations, screen rendering, and USB communication. We can compile the existing app code for Passport and run it on KeyOS, without running Ledger's proprietary operating system.

KeyOS is a microkernel operating system written in Rust, with isolated processes and sandboxed apps. We publish our operating-system source code and hardware designs so developers and security researchers can inspect how Passport works.

What's supported today

Ethereum and Solana are the first supported app families, selected for their broad adoption. Early beta users have tested compatibility with Rabby for Ethereum and EVM networks, and Phantom for Solana, over USB. We plan to add further open source Ledger apps as users and developers need them.

Legacy Mode launches in beta today as an optional, manual installation on Passport Prime. Users enter their Ledger recovery phrase on the device and connect to a compatible software wallet over USB. We welcome feedback from beta users to help improve compatibility and installation ahead of the full release this fall.

Legacy Mode is a bridge to native KeyOS apps. As developers release apps built specifically for Passport, users can install them on the same device and choose when to move beyond Legacy Mode.

What's next

The Foundation SDK is available now, and KeyOS 1.4.0 introduced app sideloading. This fall, a new KeyOS release will bring Foundation's app catalog, where users will be able to seamlessly access a growing catalog of native KeyOS apps from Foundation and third-party developers – and install them with a single tap.

To see the Switch campaign, supported apps, and installation guides, visit: 

Foundation Switch

Ledger and BOLOS are trademarks of Ledger SAS. Foundation is not affiliated with Ledger, and Legacy Mode is not sponsored or endorsed by Ledger. References to Ledger are for identification and compatibility purposes only.