Privacy, security, and threat modelling

Protect users against both cryptographic and operational failure.

Follow these 8 lessons in order, or choose the topic you need. Each lesson combines an explanation, a worked example and practice inside the Guild.

1. Common-input and change heuristics

   Chain surveillance infers ownership from transaction structure; heuristics are probabilistic, not consensus facts.

   Open lesson

2. CoinJoin

   Collaborative transactions break simple ownership heuristics but introduce coordination, amount, and operational considerations.

   Open lesson

3. PayJoin and silent payments

   Receiver-assisted construction and reusable scanning addresses reduce common transaction graph signals.

   Open lesson

4. Network privacy

   IP observation, timing, wallet queries, and address reuse can reveal links even when on-chain structure is careful.

   Open lesson

5. Hardware-wallet threat models

   Secure elements, firmware, host compromise, supply chains, and verification UX define actual signing security.

   Open lesson

6. Multisig operations

   Geographic separation and policy redundancy help only when backups, quorum availability, and change verification are practiced.

   Open lesson

7. Protocol attack surfaces

   Parsing, consensus divergence, nonce reuse, oracle manipulation, key compromise, and economic exploits require layered controls.

   Open lesson

8. Incident response

   Preparation includes detection, communication, key rotation or migration, evidence preservation, and safe recovery procedures.

   Open lesson