Trezor Suite® – Secure Integration Guide

Overview

Trezor Suite provides a secure, user-facing environment for interacting with hardware wallets. This guide outlines best practices, authentication flows, and sample code snippets to help developer teams integrate Trezor Suite functionality into partner applications while prioritizing user safety and threat resistance.

Core Principles

• Least privilege: request only the information required (e.g., address discovery vs full account export).
• Explicit user consent: every sensitive action must be authorized on-device.
• Lead with security: default to non-custodial flows and strong client-side validation.

Authentication & Session Model

Integrations should authenticate using OAuth2 or API keys for server-to-server operations. For wallet interactions, prefer short-lived session tokens and tie sessions to user action contexts. Never persist raw device data or mnemonic material server-side.

Connecting to Trezor Devices

Use the official bridge and trezor-connect library for web-based flows. For desktop applications, rely on the native Trezor connectivity libraries or platform USB interfaces with WebUSB fallback.

// Example: basic trezor-connect usage (JavaScript)
import TrezorConnect from 'trezor-connect';

TrezorConnect.init({
  connectSrc: 'https://connect.trezor.io/9/',
  popup: true,
  lazyLoad: true,
});

const getAddress = async () => {
  const result = await TrezorConnect.getAddress({
    path: "m/44'/0'/0'/0/0",
    coin: 'Bitcoin',
  });
  if (result.success) console.log('address', result.payload.address);
};

API Surface

Trezor Suite exposes secure, audited functions through trezor-connect including message signing, psbt handling, and device management. Keep the UI flow clear: show expected signing data, verify amounts and destinations, and prompt users to confirm on-device.

Security Checklist

• Use HTTPS with HSTS and strong TLS ciphers.
• Limit API key scope and rotate regularly.
• Perform input validation and canonicalization for addresses and amounts.
• Log actions for audit but never log private keys, mnemonics, or raw signatures that reveal sensitive data.
• Implement Content Security Policy (CSP) to prevent injection attacks.

Example Integration Flow

1. Initiate a connection with trezor-connect and request the minimum scope.
2. Fetch the account's addresses for display (read-only).
3. Prepare a transaction (locally build PSBT for Bitcoin).
4. Request user signature; show a clear review summary and require on-device approval.
5. Broadcast the signed transaction using your preferred backend or public node.

Handling Errors & Device States

Be explicit about device states: locked, unavailable, firmware outdated. Provide actionable UI remediation: instruct users to unlock, update firmware, or reconnect. Use graceful fallbacks if WebUSB or the bridge is unavailable.

Privacy Considerations

Minimize telemetry. If you collect usage metrics, aggregate and anonymize them, and give users an opt-out. Never associate telemetry with exported addresses or on-chain activity that can deanonymize users.

Testing & QA

Automated tests should include hardware-in-the-loop scenarios where possible, and mock device responses for CI runs. Validate your UX with real users to ensure prompts and warnings are understandable.

FAQ (Short)

Q: Can we store derived addresses server-side?
A: Yes for indexing, but store only public addresses and fingerprint metadata — never store private keys or mnemonic seeds.

Q: Is on-chain broadcasting supported?
A: Trezor signs transactions but does not broadcast; implement broadcasting via your backend or a public RPC endpoint.