diff --git a/CLOSED.md b/CLOSED.md
deleted file mode 100644
index a7e9291..0000000
--- a/CLOSED.md
+++ /dev/null
@@ -1,54 +0,0 @@
-# CLOSED
-
-**This repository is archived and closed. Development continues in
-[`Umbra-Bookshelf`](https://git.mini-eq/umbragit/Umbra-Bookshelf).**
-
-Closed: 2026-10-18
-
----
-
-## Why
-
-This repository held three separate WordPress plugins — **BD Bookshelf**,
-**BD BookShelfHelper** and **BD SimpleEmail** — that shipped the same product
-surface under three different admin menus. They were consolidated into a single
-plugin, **Umbra Bookshelf**, which now lives in its own repository.
-
-## What moved where
-
-| Was | Is now |
-|---|---|
-| `bd-bookshelf-plugin/` | `Umbra-Bookshelf/umbra-bookshelf/includes/books/` |
-| `bd-bookshelfhelper/` | `Umbra-Bookshelf/umbra-bookshelf/includes/library/` |
-| `bd-simpleemail/` | `Umbra-Bookshelf/umbra-bookshelf/includes/email/` |
-| `SPEC_BD_Bookshelf_Plugin.txt` | `Umbra-Bookshelf/umbra-bookshelf/spec/SPEC_Umbra_Bookshelf_Plugin.md` |
-| `SPEC_BD_BookHelper_Plugin.txt` | `Umbra-Bookshelf/umbra-bookshelf/spec/archive/` |
-| `bd-bookshelf/` (theme) | `Umbra-Bookshelf/theme/` — unchanged, still a separate artifact |
-
-The `v1.0.0` tag marks the final state of the consolidated plugin before the
-repository was closed.
-
-## This repository is read-only
-
-No further commits will be made. The history is preserved for provenance —
-including the original separate plugins, which are recoverable at the tags and
-commits before `dec7329`.
-
-Do not install the individual plugins from here. They were never designed to run
-together: they collide on the `bd_books` and `bd_series` tables, both register
-an admin menu, and they attach duplicate handlers to the same AJAX actions and
-cron hooks. See `Umbra-Bookshelf/umbra-bookshelf/docs/KNOWN-ISSUES.md`.
-
-## Upgrading an existing site
-
-Install **Umbra Bookshelf** from the new repository, then **deactivate** BD
-Bookshelf, BD BookShelfHelper and BD SimpleEmail in WordPress.
-
-**Deactivate, do not delete.** Deleting a plugin runs its uninstall routine,
-which drops your database tables and options. Umbra Bookshelf reads and writes
-the same table names, option keys, post meta, cron hooks and shortcodes, so
-existing data carries over untouched.
-
-The admin menu structure changed: three top-level menus became one
-**Umbra Bookshelf** menu. The full submenu map is in
-`Umbra-Bookshelf/umbra-bookshelf/spec/SPEC_Umbra_Bookshelf_Plugin.md`.
diff --git a/README.md b/README.md
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index 0000000..de2d4d3
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+++ b/README.md
@@ -0,0 +1,66 @@
+# Umbra Bookshelf
+
+The WordPress book-management solution for authors and publishers.
+
+Umbra Bookshelf began as three separate plugins — **BD Bookshelf**,
+**BD BookShelfHelper** and **BD SimpleEmail** — and is now a single consolidated
+plugin. This repository continues the history of the original
+[Bookshelf](https://git.mini-eq/umbragit/Bookshelf) repository, which is now
+closed and archived.
+
+## Repository layout
+
+| Path | What it is |
+|---|---|
+| `umbra-bookshelf/` | **The plugin.** Books, library and email modules. Start at [`umbra-bookshelf/readme.txt`](umbra-bookshelf/readme.txt). |
+| `theme/` | The `bd-bookshelf` WordPress theme. A separate artifact, deliberately **not** renamed in the consolidation. |
+| `archive/pre-umbra-releases/` | Release zips of the three pre-merge plugins. Superseded — do not install. |
+| `Old/` | Earlier plugin and theme snapshots, kept for reference. |
+| `docs/`, mockups, images, `.docx`/`.zip` specs | Design material carried over from the original repository. |
+
+## Documentation
+
+* [`umbra-bookshelf/spec/SPEC_Umbra_Bookshelf_Plugin.md`](umbra-bookshelf/spec/SPEC_Umbra_Bookshelf_Plugin.md)
+  — the authoritative specification: identity, naming rules, architecture,
+  module responsibilities, admin menu map, lifecycle.
+* [`umbra-bookshelf/docs/ARCHITECTURE.md`](umbra-bookshelf/docs/ARCHITECTURE.md)
+  — why the plugin is shaped this way.
+* [`umbra-bookshelf/docs/KNOWN-ISSUES.md`](umbra-bookshelf/docs/KNOWN-ISSUES.md)
+  — defects carried over from the merge, including one deliberately deferred.
+* [`umbra-bookshelf/spec/archive/`](umbra-bookshelf/spec/archive/) — pre-merge
+  specifications, retained for provenance only.
+
+## Development
+
+```bash
+# static checks: syntax, duplicate classes, unresolved requires and assets,
+# leftover old identifiers, preserved storage contracts
+python3 umbra-bookshelf/tests/verify_structure.py
+
+# runtime boot against stubbed WordPress (each context needs its own process)
+php umbra-bookshelf/tests/smoke_runtime.php front
+php umbra-bookshelf/tests/smoke_runtime.php admin
+```
+
+## Upgrading from the old plugins
+
+Umbra Bookshelf uses the same database tables, option keys, post meta, cron
+hooks and shortcodes as the three plugins it replaces, so existing data carries
+over without migration.
+
+Install Umbra Bookshelf, then **deactivate** BD Bookshelf, BD BookShelfHelper
+and BD SimpleEmail. Do not delete them — deleting runs their uninstall routines,
+which drop your tables and options.
+
+## Status
+
+`v1.0.0` is the first consolidated release. The most important outstanding
+problem is documented in
+[`docs/KNOWN-ISSUES.md`](umbra-bookshelf/docs/KNOWN-ISSUES.md) §1: the books and
+library modules still create `bd_books` and `bd_series` with two incompatible
+schemas. This predates the consolidation — merging the plugins made it
+unconditional, and resolving it requires a data migration.
+
+## Licence
+
+Apache-2.0 — see [`LICENSE`](LICENSE) and [`NOTICE`](NOTICE).
diff --git a/bd-bookshelf.zip b/archive/pre-umbra-releases/bd-bookshelf.zip
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rename to theme/style.css
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diff --git a/umbra-bookshelf/spec/SPEC_Umbra_Bookshelf_Plugin.md b/umbra-bookshelf/spec/SPEC_Umbra_Bookshelf_Plugin.md
index a345f3b..b967180 100644
--- a/umbra-bookshelf/spec/SPEC_Umbra_Bookshelf_Plugin.md
+++ b/umbra-bookshelf/spec/SPEC_Umbra_Bookshelf_Plugin.md
@@ -73,7 +73,7 @@ post content. Renaming any of them silently orphans existing data.
 One legacy PHP class name is retained by design: `class-umbra-theme-compatibility.php`
 declares `Umbra_Theme_Compatibility` and then
 `class_alias('Umbra_Theme_Compatibility', 'BD_BookShelfHelper')` so the
-unmodified `bd-bookshelf` theme's static `BD_BookShelfHelper::` calls keep working.
+unmodified `theme/` (bd-bookshelf) theme's static `BD_BookShelfHelper::` calls keep working.
 
 ---