Bitcoin threat models, without the magic

Articles on Security

Long-form, source-linked analysis of Bitcoin wallets, tools, network behavior, attack surfaces, and the tradeoffs behind serious self-custody.

Lightning and Self-Custody

Primal Wallet for Beginners: Zaps, Lightning, and a COLDCARD Backup

A beginner guide to Primal's self-custodial Spark wallet, Lightning payments and zaps, with an optional COLDCARD Seed Vault recovery copy.

Bitcoin Tools

Why mempool.space Matters for Bitcoin Users

How mempool.space makes Bitcoin fees, pending transactions and blocks visible, why self-hosting matters, and how COLDCARD NFC PushTx works with it.

Lightning and Self-Custody

Lightning for Beginners: BULL Wallet for Spending, COLDCARD for Savings

A beginner guide to Lightning payments with BULL Wallet, its Liquid tradeoffs, and moving larger savings to COLDCARD cold storage.

Hardware Wallet Security

Why an Air-Gapped Computer Is Not Enough

Why taking a Bitcoin computer offline does not solve malicious software, key isolation, trusted displays, recovery, stress, or coercion.

Hardware Wallet Security

A Raspberry Pi Is Still a Computer: Why Bitcoin Needs a Purpose-Built Hardware Wallet

A balanced look at Raspberry Pi, ESP32, stateless signers, evil-maid attacks, and why long-term savings need purpose-built hardware.

Hardware Wallet Security

A Clean Phone Is Still a Computer: Why Serious Bitcoin Needs a Hardware Signer

Why a wiped phone still lacks the key isolation, trusted display, narrow attack surface, and physical defenses of a purpose-built Bitcoin signer.

Hardware Wallet Security

Offline Is Not Enough: COLDCARD vs a Disconnected Phone

How COLDCARD separates Bitcoin keys and transaction approval from a phone or computer that may already be compromised.