claude-dev-suite Ledger Hardware Wallets
Ledger (France) — second-most popular hardware wallet line. Models based on Secure Element (SE) chips.
Models
| Model | Year | Notes |
|---|---|---|
| Nano S | 2016 (deprecated) | First popular Ledger; SE + MCU |
| Nano X | 2019 | Bluetooth, larger screen |
| Nano S Plus | 2022 | Successor to Nano S, more memory |
| Stax | 2023 | Touchscreen, e-ink |
| Flex | 2024 | Color touchscreen |
BOLOS architecture
Ledger devices run BOLOS (Blockchain Open Ledger Operating System). Each cryptocurrency has a separate app loaded onto the device:
- Bitcoin app (
bitcoin-app-developer) - Ethereum app
- Various altcoins.
App switching during use (close old, open new). Apps signed by Ledger.
Bitcoin app
Functions:
- Get xpub at any path.
- Generate addresses.
- Sign txs (legacy mode).
- Sign PSBTs (modern mode, since v2.0+).
Connection
- USB (HID).
- Bluetooth (Nano X / Stax / Flex).
- Ledger Live (desktop / mobile).
- Third-party: HWI, Sparrow, Specter, Electrum, Wasabi.
Anti-klepto
Defense against compromised firmware leaking the seed via deterministic-looking signatures (DUSEC attack):
- Host provides random
aux_rand. - Device combines with internal randomness.
- Final nonce derivation uses both → tamper-evident if firmware tries to leak seed.
Recovery service (controversial)
In May 2023, Ledger announced "Recover" — optional opt-in service that splits seed into encrypted shards stored by 3rd parties. Backlash: critics argued device firmware can extract seed.
Legitimate users can opt-out / never enable.
API
ledger-bitcoin (Python):
from ledger_bitcoin import Client, ChainID
with Client(transport=connect_hid_or_ble(), chain=ChainID.MAIN) as client:
pk = client.get_extended_pubkey("m/84'/0'/0'")
psbt_signed = client.sign_psbt(psbt, wallet_policy, hmac=None)
JavaScript: @ledgerhq/hw-app-btc.
PSBT support
Modern Ledger (v2+) supports PSBT directly. Older Ledger requires legacy "raw tx + path" flow.
Multi-sig: Ledger requires "wallet policies" — registered descriptor on the device with HMAC for trust binding.
Common issues
- Wrong app: app for different chain open instead of Bitcoin.
- Path mismatch: Ledger Live defaults to BIP44 even for segwit; third-party tools must override to BIP84/86.
- Bluetooth Nano X: occasional connection drops, prefer USB.
- Wallet policy registration: required for multisig; first-time setup confusing.