# Paper 16 related-work ledger

Status: paper-local author ledger; not peer review

Date: 23 July 2026

## Categorical database semantics

| Sources | Established result used | CatDB boundary |
|---|---|---|
| `maclane1998categories` | Categories, functors, identity, and associativity supply the mathematical vocabulary. | Paper 16 claims no new category-theory law. |
| `spivak2012functorial` | A schema can be modeled as a category, an instance as a set-valued functor, and a schema mapping can induce three data-migration functors. | Accepted Slice 2 implements no instance semantics or migration functor. |
| `spivak2015relational` | Functorial data migration has an established relational account. | Paper 16 does not establish relational compilation or backend equivalence. |
| `schultz2017integration`, `schultz2017algebraic` | Algebraic database and data-integration systems already provide executable categorical semantics with equations and mappings. | The accepted CatDB result is a smaller repository-specific profile, not a replacement for or theoretical advance over this work. |
| `cql2026` | CQL is an existing executable categorical database language. | CatDB's Haskell package is a reference implementation for shared fixtures, not the first executable categorical database system. |

## Schema mappings and data exchange

| Sources | Established result used | CatDB boundary |
|---|---|---|
| `fagin2005exchange` | Data exchange has established semantics for mappings, solutions, and query answering. | Paper 16 has no universal-solution or query-answering result. |
| `fagin2005composition` | Composition of schema mappings is an established database-theory problem. | CatDB's accepted composition is finite path substitution inside one declared profile, not a general mapping-composition theorem. |

## Executable checking and differential evidence

| Sources | Established result used | CatDB boundary |
|---|---|---|
| `marlow2010haskell`, `aeson2026` | Haskell and Aeson provide the language and closed JSON-codec mechanisms used by the reference package. | Language choice does not confer semantic authority. |
| `claessen2000quickcheck` | QuickCheck supplies randomized property testing with reproducible replay support. | The accepted seven properties and 1,550 trials are bounded computational evidence, not proof. |
| `runciman2008smallcheck` | SmallCheck makes exhaustive testing over small values an explicit alternative to random generation. | Paper 16 does not claim exhaustive coverage. |
| `mckeeman1998differential` | Differential testing predates CatDB's Rust/Haskell comparator. | The project-specific contribution is its closed fixture protocol and evidence bookkeeping, not differential testing itself. |
| `cabal2026`, `ghc2026warnings` | Official Cabal and GHC documentation defines project freezing and strict warning behavior. | A successful build does not prove the model or preserve an unpinned historical dependency graph forever. |
| `rfc6901`, `rfc8259`, `rfc8785` | JSON, JSON Pointer, and JSON canonicalization have published interoperability rules. | Slice 2 uses parsed-value round trips and typed diagnostics; it does not claim complete JSON-edge coverage. |

## Repository evidence records

| Sources | Established result used | CatDB boundary |
|---|---|---|
| `catdbslice2`, `catdbslice2review` | The accepted Slice 2 release and independent code review fix the historical source, corpus, counts, hashes, findings, and pass verdict. | These are project evidence records, not external prior art or mathematical proof. |
| `catdbslice4` | The later accepted Slice 4 release fixes the 33-case finite-instance and bounded-Delta boundary. | It is reported separately and never backdated into the primary Slice 2 result. |

## Disposition

The paper's defensible delta is repository-specific: a compact Haskell
semantic oracle and research compiler for a named CatDB profile, closed shared
fixtures, deterministic property tests, source-audited independence from Rust
and fixture expected values, exact golden gates, and a computed-output
comparison. Its use as a property-testing reference is an engineering role.
It is neither a production dependency nor proof authority.