Start Here: Foundations
Bitcoin Threat Models
Security starts by defining the adversary. Are you protecting against a burglar, a house fire, an exchange collapse, or your own memory failure?
Zero-to-Cypherpunk
A definitive, step-by-step checklist for moving off exchanges, verifying hardware wallet firmware, and establishing a secure baseline.
Recovery Drills 101
A backup isn't a backup until you've successfully restored it. Learn how to safely wipe your device, recover the seed, and verify your addresses.
Offline Cryptographic Tools
Seed & Passphrase
Generate a high-entropy seed phrase via physical dice rolls, calculate checksums locally, and instantly preview hidden wallets.
BIP-85 Child Seed
Generate multiple deterministic child seed phrases from a single master seed using the BIP-85 hierarchical standard.
Output Descriptor
Generate watch-only wallet descriptors (Native SegWit, Taproot, Multisig) directly from air-gapped seed entropy.
Seed XOR Calculator
Split a BIP-39 seed phrase into 2–4 distinct cryptographic shares using secure offline XOR logic.
Encrypted Workspace
Save clear text or AES-256-GCM encrypted data (like output descriptors) as portable .skb files for secure transport.
SeedQR Generator
Create and verify hand-drawn, air-gapped seed backups on a 29x29 printable master grid for robust physical storage.
Visual Designer
Design your Bitcoin self-custody architecture visually. Choose Single-Sig, Multisig, or XOR and generate a printable security diagram.
Optical Data Transfer
Bridge the air-gap natively. Transmit or receive any file type across devices offline using high-speed animated QR codes.
Offline Signer
Sign partially signed Bitcoin transactions (PSBTs) entirely offline, enabling a secure air-gapped signing workflow without exposing keys.
OpSec & Physical Security
Estate Planning
Downloadable templates and OpSec strategies for passing your Bitcoin to heirs without compromising your seed phrase while alive.
Geographic Redundancy
How to safely distribute physical backups across multiple locations without creating single points of failure.
Steel Stress Tests
A curated breakdown of the best physical metal storage solutions, analyzing resistance to house fires, crushing, and corrosion.
Technical Concepts
XOR vs. Multisig
A deep dive into the technical tradeoffs between splitting a seed at the base cryptographic layer (XOR) versus on-chain Multi-Signature setups.
Air-Gapped Workflows
Master the art of signing transactions without an internet connection using PSBTs, QR codes, and microSD cards.
Coin Control & UTXOs
Why treating Bitcoin like digital cash improves your on-chain privacy, and how to manage UTXOs to save on future transaction fees.