diff --git a/README.adoc b/README.adoc
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-// SPDX-License-Identifier: CC-BY-SA-4.0
-// Copyright (c) Jonathan D.A. Jewell <j.d.a.jewell@open.ac.uk>
-// SPDX-FileCopyrightText: 2026 Jonathan D.A. Jewell <j.d.a.jewell@open.ac.uk>
-= homebrew-tap
-:toc: preamble
-:icons: font
-:author: Jonathan D.A. Jewell
-:email: j.d.a.jewell@open.ac.uk
-
-*Homebrew tap for hyperpolymath CLI tools.*
-
-image:https://img.shields.io/badge/OpenSSF-Best_Practices-green?logo=opensourcesecurity[OpenSSF Best Practices,link="https://www.bestpractices.dev/en/projects/new?repo_url=https://github.com/hyperpolymath/homebrew-tap"]
-image:https://img.shields.io/badge/License-MPL_2.0-blue.svg[License: MPL-2.0,link="https://opensource.org/licenses/MPL-2.0"]
-image:https://api.thegreenwebfoundation.org/greencheckimage/github.com[Green Web,link="https://www.thegreenwebfoundation.org/green-web-check/?url=github.com"]
-image:https://img.shields.io/badge/homebrew-tap-yellow.svg[Homebrew tap]
-
-== What this is
-
-This is the official https://brew.sh[Homebrew] tap for hyperpolymath tools.
-It lets macOS (and Linux) users install hyperpolymath binaries via `brew`
-without manual compilation.
-
-== Install
-
-[source,bash]
-----
-# Add the tap once
-brew tap hyperpolymath/tap
-
-# Install BoJ server (cartridge-based MCP server)
-brew install boj-server
-----
-
-== Available formulae
-
-[cols="1,2,2", options="header"]
-|===
-| Formula | Installs | Source
-
-| `boj-server`
-| Bundle of Joy MCP server — 53 formally verified domain cartridges
-| https://github.com/hyperpolymath/boj-server[hyperpolymath/boj-server]
-|===
-
-== Repository layout
-
-[cols="2,3", options="header"]
-|===
-| Path | What it contains
-
-| `Formula/boj-server.rb`
-| Homebrew formula: install recipe, test block, and dependency declarations
-
-| `contractiles/`
-| Contractile validation rules (RSR standard)
-|===
-
-== Notes for maintainers
-
-The `boj-server.rb` formula contains a `sha256 "UPDATE_ON_RELEASE"` placeholder
-that must be replaced with the actual tarball SHA-256 when cutting a release.
-Run `sha256sum <tarball>` or use `brew fetch --build-from-source` to obtain it.
-
-See link:EXPLAINME.adoc[EXPLAINME.adoc] for the full implementation map.
-
-== License
-
-This project is licensed under the Mozilla Public License, v. 2.0. See the `LICENSE` file for details.
-
-SPDX-License-Identifier: CC-BY-SA-4.0
-
-== Author
-
-Jonathan D.A. Jewell +
-j.d.a.jewell@open.ac.uk
diff --git a/README.md b/README.md
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+<!--
+SPDX-License-Identifier: CC-BY-SA-4.0
+SPDX-FileCopyrightText: 2025-2026 Jonathan D.A. Jewell <j.d.a.jewell@open.ac.uk>
+-->
+
+**Homebrew tap for hyperpolymath CLI tools.**
+
+[![OpenSSF Best Practices](https://img.shields.io/badge/OpenSSF-Best_Practices-green?logo=opensourcesecurity)](https://www.bestpractices.dev/en/projects/new?repo_url=https://github.com/hyperpolymath/homebrew-tap)
+[![License: MPL-2.0](https://img.shields.io/badge/License-MPL_2.0-blue.svg)](https://opensource.org/licenses/MPL-2.0) <embed
+src="https://api.thegreenwebfoundation.org/greencheckimage/github.com"
+data-link="https://www.thegreenwebfoundation.org/green-web-check/?url=github.com" />
+![Homebrew tap](https://img.shields.io/badge/homebrew-tap-yellow.svg)
+
+# What this is
+
+This is the official [Homebrew](https://brew.sh) tap for hyperpolymath
+tools. It lets macOS (and Linux) users install hyperpolymath binaries
+via `brew` without manual compilation.
+
+# Install
+
+```bash
+# Add the tap once
+brew tap hyperpolymath/tap
+
+# Install BoJ server (cartridge-based MCP server)
+brew install boj-server
+```
+
+# Available formulae
+
+| Formula | Installs | Source |
+|----|----|----|
+| `boj-server` | Bundle of Joy MCP server — 53 formally verified domain cartridges | [hyperpolymath/boj-server](https://github.com/hyperpolymath/boj-server) |
+
+# Repository layout
+
+| Path | What it contains |
+|----|----|
+| `Formula/boj-server.rb` | Homebrew formula: install recipe, test block, and dependency declarations |
+| `contractiles/` | Contractile validation rules (RSR standard) |
+
+# Notes for maintainers
+
+The `boj-server.rb` formula contains a `sha256` `"UPDATE_ON_RELEASE"`
+placeholder that must be replaced with the actual tarball SHA-256 when
+cutting a release. Run `sha256sum` `<tarball>` or use `brew` `fetch`
+`--build-from-source` to obtain it.
+
+See <a href="EXPLAINME.adoc" class="adoc">EXPLAINME</a> for the full
+implementation map.
+
+# License
+
+This project is licensed under the Mozilla Public License, v. 2.0. See
+the `LICENSE` file for details.
+
+SPDX-License-Identifier: CC-BY-SA-4.0
+
+# Author
+
+Jonathan D.A. Jewell\
+[j.d.a.jewell@open.ac](j.d.a.jewell@open.ac).uk