Browser-based isogeny cryptography demo — elliptic curve isogenies, toy SIDH key exchange over GF(71), supersingular isogeny graph with random walk, Castryck-Decru torsion-leak attack (August 2022), CSIDH and SQIsign survivors. The scheme that fell and the math that survived. No backends. No simulated math.

cryptography elliptic-curves supersingular post-quantum sidh isogeny sike crypto-lab csidh castryck-decru sqisign

• Updated Apr 18, 2026
• TypeScript