what is libsodium-schnorr fr?

libsodium-schnorr is a C library implementing the Schnorr signature scheme, a well known way of proving you hold a secret key by producing a short signature, based on the secp256k1 curve used by Bitcoin, with added support for the ed25519 curve. On top of standard Schnorr signing and verifying, the project adds its own additional constructions: a custom hash function based on the golden ratio, and a scheme the author calls fractal signature trees, made of recursive layers of grouped signatures with a self healing feature meant to detect and repair broken parts of the tree. The core signing and verification functions are written in C and depend on OpenSSL for the secp256k1 elliptic curve math, with libsodium as an optional dependency if you want ed25519 support. According to the README, the project reaches roughly 450 signatures per second on the author's own Ryzen 5 test machine, and the author reports test videos covering an overall test suite, a deeper look at the fractal tree feature, and a stress test that reached 300,000 signatures before timing out at the fifteen minute mark. Several papers referencing this work are listed as submitted, not yet published, to a cryptography preprint archive. The README itself is upfront about its limits: single threaded signing speed is capped at a few hundred per second, the million signature stress test has not been completed, ed25519 support currently depends on an external libsodium install rather than a built in implementation, the custom golden ratio hash function is not a recognized or standardized algorithm and is suggested only for non critical uses, deep fractal trees can use a lot of memory, and the mathematical claims have not yet been checked by an outside security audit. To try it, you clone the repository and compile the core Schnorr code directly with gcc, linking against OpenSSL. The project is released under the MIT license.