Silent Shard Duo
Silent Shard Duo is a mobile SDK for MPC wallets you run on your own infrastructure. The signing key is split between the user's mobile device and your Duo Server, and the two sign together, so no single machine ever holds the whole key and users never handle a seed phrase.
Get started
Pick your framework and follow its Quickstart. Each one runs against the hosted demo server, so you can generate a key and sign in minutes without deploying anything first.
You'll need SDK access: a registry token to install the packages, and a Duo Server. Prototype against the demo server referenced in each Quickstart, or run your own; see Duo Server. For how the pieces fit together, see Key Concepts.
How Duo works
Duo has two parts you run together: a Duo Server, the second signing party deployed on your infrastructure, and a mobile SDK for your app. The second party is usually the Duo Server, but it can also be a second user device, giving a fully self-custodial mobile-to-mobile setup.
Steps
- Deploy the Duo Server as the second signing party, or use the hosted demo server to start.
- Add the SDK to your app, point it at the server endpoint, and plug in a storage client to hold keyshares.
Advantages
- No seed phrase: wallets are created by key generation, so users never record one.
- No single point of compromise: a breach of either the device or the server alone cannot produce a signature, so it cannot make an unauthorized transaction.
- Configurable custody: device plus server, or two user devices for full self-custody.
- Audited and open source: the DKLS23 protocol has completed 8 independent audits (Cure53, Trail of Bits, HashCloak, Secfault).
- Multi-chain: one SDK signs for EVM chains, Bitcoin, and Solana.
- Optional Auth Service: user management and access control. See the Auth Service guide.
Supported schemes
For the signature schemes and chains each SDK supports, see Supported Features and Chain Support.
Cookbook
Practical guides and integration examples to help you build with Silent Shard Duo.
