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README.md

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+// SPDX-License-Identifier: MPL-2.0
+= a2ml-haskell
+Jonathan D.A. Jewell <j.d.a.jewell@open.ac.uk>
+:toc:
+:toc-placement: preamble
+
+Haskell library for parsing and rendering A2ML (Attested Markup Language)
+— attestation-native markup carrying trust metadata, cryptographic
+attestation fields, and provenance information.
+
+== Overview
+
+`a2ml-haskell` provides a purely functional parser and renderer over `Text`:
+
+* `Data.A2ML.Parser` — `parseA2ML :: Text -> Either ParseError Document`.
+  Line-oriented, no regex, no mutable state. Recognises headings, multi-line
+  directive blocks (`@name: ... @end`), bullet lists, and inline formatting.
+
+* `Data.A2ML.Renderer` — serialises a `Document` back to canonical A2ML.
+
+* `Data.A2ML.Types` — `Document`, `Block`, `Inline`, `DirectiveName`
+  (typed sum: `DirAbstract`, `DirRefs`, `DirAttestation`, `DirMeta`,
+  `DirCustom Text`), `Attestation`, `TrustLevel`, `Manifest`, `Reference`.
+
+The Haskell variant uses richer directive syntax than `a2ml-rs`: directives
+are multi-line `@name: ... @end` blocks (not single-line `@name value` pairs).
+
+== Attestation Model
+
+The `Attestation` type carries:
+
+* `attestationSigner` — identity of the signing agent or person
+* `attestationAlgorithm` — e.g. `"ed25519"` or `"sha256"`
+* `attestationSignature` — hex or base64 signature (opaque, not verified here)
+* `attestationTimestamp` — optional ISO-8601 timestamp
+
+`TrustLevel` encodes attestor count and independence: `Unsigned` →
+`SelfAttested` → `ThirdPartyAttested` → `MultiAttested`.
+
+`Manifest` aggregates title, author, version, SPDX license, overall trust
+level, and the full attestation list — the entry point for provenance
+inspection.
+
+== Building
+
+[source,sh]
+----
+cabal build
+cabal test
+----
+
+== Related
+
+* link:https://github.com/hyperpolymath/a2ml-rs[a2ml-rs] — Rust implementation
+* link:https://github.com/hyperpolymath/pandoc-a2ml[pandoc-a2ml] — Pandoc Lua reader/writer
+
+== License
+
+MPL-2.0. See link:LICENSE[LICENSE].