Open source · the coordinate system

Topon.
Every input gets a place.

A hash whose output has geometry. Places have distances.

What it is

A hash that answers a different question.

A traditional hash tells you whether two things are the same, and nothing more. Topon maps input to a point on a Riemannian manifold, so the output carries geometry: distance, containment, hierarchy, interpolation. The name is from τοπος, place. It turns names into positions.

Deterministic by construction

Structural, not disciplined.

Determinism does not come from being careful with floating point. It comes from there being none: no f32 or f64 appears in any hash path. All arithmetic is gMath fixed point, so a stored coordinate means the same thing on every machine that reads it.

Three modes

One trait, three hashers.

Domain. Names into positions, built for domain names. The best distribution metrics of the three.

Speed. Arbitrary bytes, throughput first. A one-byte change anywhere avalanches rather than decays.

Hierarchical. Trees walked into hyperbolic space along geodesics. Children sit near their parents, so a taxonomy keeps its family structure as plain distance.

What it is not

Not a cryptographic hash.

SHA-256 answers "are these the same?". Topon answers "how far apart are these?". It makes no preimage or adversarial-collision claims. Use both, for different questions.

By the numbers
3
modes: Domain, Speed, Hierarchical
3
manifolds: sphere, Euclidean, hyperbolic
0
floats in any hash path
4
public items; everything else is internal

All distances geodesic, never chordal. Apache-2.0.