# Paper 15 related-work ledger

Evidence boundary: accepted Slice 4 commit
`056915834fcc2f172a4a72efe3629f4f753e45cf`. Later working-tree changes are
excluded.

| Citation key | Area | Relation to Paper 15 | CatDB delta supported now | Status |
|---|---|---|---|---|
| `spivak2012functorial` | categorical databases | Defines schemas, instances, mappings, and induced migration functors. | A bounded Rust implementation of finite validation, mapping composition, and Delta over the CatDB fixture profile. | prior theory; CatDB evidence is computational |
| `spivak2015relational` | relational compilation | Connects functorial migration to relational operations. | No CatDB backend lowering exists. | relevant prior art; systems delta obstructed |
| `schultz2017integration` | algebraic integration | Gives an executable algebraic integration framework. | Closed cross-language fixture contract and structured diagnostics are repository-specific; broad novelty is unestablished. | prior implementation and theory |
| `schultz2016algebraic` | typed algebraic databases | Treats types and equations in algebraic database presentations. | CatDB's admitted serialized profile is narrower. | prior theory |
| `cql` | categorical implementation | Existing categorical query and integration tooling; the project distinguishes itself from a DBMS. | Rust implementation language and shared Rust/Haskell/Lean evidence do not alone establish novelty. | direct implementation comparator |
| `catlab` | categorical implementation | Provides categorical algebra, finite presentations, and attributed C-sets in Julia. | CatDB has a different bounded runtime contract, not a demonstrated capability advantage. | direct implementation comparator |
| `jung2018rustbelt` | Rust safety | Formal account of Rust's safety foundations and unsafe extensions. | Supports only a scoped language-level safety statement. | prior literature |
| `rustownership` | Rust language | Documents ownership and borrowing. | Explains an implementation choice; does not prove CatDB semantics. | official documentation |
| `cargoworkspaces` | Rust build organization | Documents Cargo workspace behavior. | Supports the six-crate workspace description, not research novelty. | official documentation |
| `serdecontainer` | serialization | Documents `deny_unknown_fields`. | Supports the closed JSON boundary mechanism, not semantic completeness. | official documentation |
| `graefe1994volcano` | execution engines | Defines an extensible operator-model lineage. | CatDB has no operator engine at Slice 4. | future systems comparator |
| `graefe1995cascades` | query optimization | Defines a rule-based optimizer framework. | CatDB has no optimizer or memo at Slice 4. | future systems comparator |
| `sqliteplanner` | physical planning | Documents SQLite plan selection. | No CatDB SQLite lowering or comparison exists. | future backend baseline |
| `postgresplanner` | physical planning | Documents PostgreSQL planning and optimization. | No CatDB PostgreSQL lowering or comparison exists. | future backend baseline |
| `datafusion` | Rust query engine | Provides logical and physical optimization and Arrow execution in Rust. | A future CatDB contribution must be semantic obligations on planning, not merely Rust or an IR. | strongest current systems comparator |
| `tokio` | asynchronous Rust | Provides tasks, scheduling, I/O, and synchronization. | Tokio is absent from Slice 4; cancellation and backpressure remain unspecified. | candidate technology only |
| `arrowformat` | data interchange | Defines a columnar memory and interchange format. | Arrow is absent from Slice 4. | candidate technology only |
| `wasmcore` | portable execution | Defines WebAssembly core semantics. | No CatDB WASM build or host contract exists. | deployment baseline |
| `wasmtime` | WebAssembly host | Documents a Rust embedding API. | Wasmtime is absent from Slice 4. | candidate technology only |

The manuscript cites all nineteen entries. “Written in Rust,” “uses an IR,”
and “implements categorical mappings” are not treated as novel contributions
without a demonstrated delta from these systems.