What is Trézór Bridge®™?
Trézór Bridge®™ is a lightweight, auditable bridge protocol and SDK designed to provide resilient, secure, and user-friendly connectivity between client wallets and remote crypto services. Built on modern cryptographic primitives and privacy-preserving transport, Bridge minimizes the attack surface while maximizing control for the wallet holder.
Key Features
- Zero-Knowledge Session Establishment — ephemeral sessions are negotiated with minimal metadata leakage, preventing long-lived identifiers that correlate activity across services.
- Local Signing, Remote Submission — private keys remain in the wallet for signing. Bridge sends only signed payloads for broadcasting and optional relayer services.
- Deterministic Recovery — safe reconnection flows let users recover pending operations if connectivity drops, without exposing secret material.
- Policy-Driven Permissions — granular permission prompts let users approve capabilities per session (read-balance, sign-transaction, view-address, etc.).
- Multi-Chain Support — modular adapters for EVM, UTXO, and future chains allow broad interoperability.
Security Principles
- Principle of Least Privilege — only the minimal request and approvals necessary for a task are requested from the user.
- Transparent Cryptography — algorithms and protocol flows are documented and auditable; no hidden or proprietary key handling.
- Replay & Man-in-the-Middle Protections — off-the-shelf secure transport and nonce-handling protect signed messages against replay and tampering.
- Opt-In Telemetry — all telemetry is user-consent based, anonymized, and aggregate-only by default.
Why wallets choose Trézór Bridge®™
Wallets and services pick Bridge because it balances three things that are usually at odds: security, developer ergonomics, and user experience. Engineers can integrate with a mature SDK and clear API, while product designers get a predictable and non-intrusive UX. Most importantly, users keep custody of their keys — Bridge merely helps signed transactions and authenticated messages travel efficiently and securely.
"We use Trézór Bridge®™ to give users the speed of cloud-backed services without giving up private key custody." — Product Lead, Wallet A
How Trézór Bridge®™ Works — at a glance
- Handshake: Wallet and service perform a mutual authentication handshake using ephemeral keys. No long-lived session tokens are stored by default.
- Capability Exchange: Service requests the minimum capabilities. Wallet displays a clear, contextual prompt describing the scope and duration.
- Local Authorization: User approves. Wallet signs payloads locally; the signature is returned to the service or relayer for submission.
- Submission & Monitoring: Signed transactions are relayed to the network. Optional encrypted receipts are returned to the wallet for confirmation and safe UI state update.
- Disconnect & Forget: Sessions expire automatically; wallets can explicitly revoke access and the service must delete ephemeral state on confirmation.
// Wallet SDK (light)
const bridge = new TrezorBridge({env: 'production'});
// 1. Initiate handshake
const session = await bridge.startSession({chain: 'ethereum'});
// 2. Receive capability request
const request = await session.receiveRequest();
// show permission UI -> user approves
// 3. Sign
const signed = await wallet.sign(request.payload);
// 4. Send signed payload
await session.sendSigned(signed);
// 5. Session auto-expires
The SDK is intentionally small; responsibilities for broadcasting, indexing, and optional relaying live outside the wallet so wallets remain thin, auditable, and upgradable.
Integration & Developer Experience
Trézór Bridge®™ ships with concise SDKs for web, mobile, and server environments. The API focuses on predictable, testable flows so integrators can write deterministic UI and handle edge cases like partial connectivity gracefully.
Key integration highlights
- Single-file SDK — easy npm import or CDN fallback for web wallets.
- TypeScript types — strongly-typed request/response models for safer integrations.
- Emulator & Testnet modes — rapid developer loops with logs and deterministic replay for QA.
- Policy hooks — allow teams to enforce corporate approval flows for custodial or enterprise deployments.
Documentation includes quickstart guides, UX copy examples for permission prompts, and security recommendations for both wallets and services.
Privacy & Compliance
Privacy is a core design constraint: Bridge avoids persistent identifiers, collects only telemetry necessary to operate the service (and then only with consent), and supports encryption-at-rest for optional relay metadata. For teams operating in regulated jurisdictions, Bridge provides configuration knobs that allow minimizing data retention and generating audit reports without exposing user secrets.
Options for compliance teams
- Configurable retention windows for relayer logs
- Exportable, aggregated telemetry for compliance audits
- Policy-driven consent recording (no secrets stored)
Real-world use cases
- dApp Wallet Connect: Seamless UX for connecting to decentralized exchanges and NFT marketplaces while preserving private key custody.
- Gas & Fee Abstraction: Securely request paymaster approval flows without exposing wallet secrets; signed approvals are relayed for payment.
- Enterprise Signing Workflows: Multi-signature orchestration and safe recovery for corporate wallets interfacing with on-chain governance systems.
- Hardware Wallet Gateways: Thin bridge layer that translates hardware signing requests into standardized payloads for many chains.
FAQ
Does Trézór Bridge®™ ever see private keys?
No. Private keys never leave the wallet. Bridge only routes signed payloads and manages ephemeral session state.
What happens if my device goes offline mid-transaction?
Bridge provides safe reconciliation: transactions that were signed but not broadcast can be recovered (by transaction hash or signed envelope) so users don’t lose state or accidentally re-sign the same intent.
Is Bridge audited?
Yes — the core protocol and reference implementations are designed for third-party audit and continuous fuzzing. Audit reports and security advisories are published for integrators to review.
Get started
Whether you run a consumer wallet, hardware device, or a custodial service, Trézór Bridge®™ gives you an easy integration path toward secure, privacy-preserving connectivity.
Explore the SDK • Try the demo