catgraph workspace

Category-theoretic graph structures in Rust. The catgraph crate (v0.12.0, slim baseline) is a strict Rust implementation of Fong & Spivak, Hypergraph Categories (2019). Applied-CT extensions (catgraph-applied v0.5.2) track Fong & Spivak, Seven Sketches in Compositionality (2018). Wolfram-physics extensions live in a third sibling workspace crate.

Members

Crate	Path	Purpose
`catgraph` v0.12.0	`catgraph/`	Strict Fong-Spivak 2019 paper implementation: cospans, spans, Frobenius algebras, hypergraph categories, Theorem 1.2 equivalence, spider theorem (Thm 6.55), `Corel<Λ>` (F&S 2018 Ex 6.64; v0.12.0), `Cospan::compose_with_quotient` additive API, `parallel` feature (WASM + native, W.1)
`catgraph-physics` v0.2.2	`catgraph-physics/`	Wolfram-physics extensions: hypergraph DPO rewriting, multiway evolution, gauge theory, branchial spectral analysis
`catgraph-applied` v0.5.2	`catgraph-applied/`	Applied CT extensions. Tier 1 (v0.3.x): generic `DecoratedCospan<F>` (Def 6.75, Thm 6.77), Petri nets as hypergraph category, wiring diagrams, E_n operads, Temperley-Lieb, linear combinations. Tier 2 (v0.4.0): props + `Free(G)` (Def 5.2, 5.25), `OperadAlgebra` with Circ (Def 6.99, Ex 6.100), `OperadFunctor` with canonical E₁↪E₂ (Rough Def 6.98). Tier 3 (v0.5.x): `Rig` + 4 concrete rigs (Def 5.36), `SignalFlowGraph<R>` (Def 5.45), `MatR<R>` (Def 5.50), `sfg_to_mat` functor (Thm 5.53), `Presentation<G>` with CC decision engine + Layer-1 Joyal-Street NF short-circuit, `EnrichedCategory<V>` + `LawvereMetricSpace<T>`, `CompleteFunctor<G>` + `MatrixNFFunctor<R>` closing Thm 5.60 semantically (v0.5.2)

These are separate repos that depend on catgraph and/or catgraph-physics:

Repo	Purpose
catgraph-surreal	SurrealDB persistence layer for catgraph and catgraph-physics types
irreducible	Computational irreducibility framework (Gorard 2023) using catgraph and catgraph-physics

cargo build --workspace
cargo test --workspace
cargo clippy --workspace -- -W clippy::pedantic

Each crate has its own README and CLAUDE.md:

MIT — see LICENSE.