Durability Across Cryptographic Regime Change

What does it mean for a digital monetary system to be durable? In particular, durable across the cryptographic regime change that is now visible on the horizon?

The system survives the migration to post-quantum primitives.

Durability means the system continues to satisfy stability, privacy, and fairness across changes in the cryptographic primitives the system uses. Specifically, the system must support migration from current proof systems and signatures to post-quantum primitives without invalidating the on-chain history of holders' positions, attestations, or commitments.

In StableZK, the migration path is staged:

• Phase 1 production primitives today (Groth16, BLS12-381, Ed25519, ECDH-threshold).
• Phase 2 hybrid hash-based commitments alongside the classical proofs and signatures, for high-value operations.
• Phase 3 STARK or lattice-based primitives end-to-end, with re-attestation primitives so that proofs generated under Phase 1 can be replayed under Phase 3 against the same underlying state.

Durability is the property the existing stablecoin ecosystem has the worst position on. Every stablecoin in production today depends on classical cryptographic primitives that will, on a date no one can announce, become forgeable. The default migration plan in the industry is "we'll figure it out." That plan has the same character as the stability plans Chapter 4 critiques.

• Ch. 3 · Cryptographic Primitives — the migration phases in detail
• § 6.5 · Re-attestation Under Primitive Change — the user-side mechanics of the migration