diff --git a/CHANGELOG.md b/CHANGELOG.md
index aeaee7e..d72e5df 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -4,6 +4,47 @@ All notable changes to this project will be documented in this file.
 
 The format is based on [Keep a Changelog](https://keepachangelog.com/en/1.1.0/).
 
+## [0.21.0] - 2026-09-25
+
+### Added
+- `Modules\Core\File` — a generic, storage-backend-agnostic file registry: `Models\File` (a
+  `files` table row per stored file — disk, path, original name, mime, size, a `purpose` tag,
+  and a nullable polymorphic owner), `Services\FileService` (store/retrieve/download/exists/
+  delete/list/`pruneUnowned`, delegating every actual byte-level operation to a
+  `Contracts\FileAdapterInterface` resolved per disk — `Adapters\LocalFileAdapter` today, the
+  same contextual-binding pattern `Shipping\Contracts\CarrierFulfillmentInterface` already uses
+  per carrier, so a future `S3FileAdapter` is one class and one more match arm, nothing else
+  changes), and `Http\Controllers\DownloadFileController` — a signed-URL-only route
+  (`files.download`) any consuming app can mint a link to, serving either inline (a preview) or
+  as a forced download (`?download=1`).
+- `Modules\Core\File\Http\Controllers\UploadFileController` — an abstract base for "accept an
+  upload, validate it, store it via `FileService`, return its id" endpoints. Which
+  extensions/sizes are acceptable is deliberately left to a concrete subclass's own
+  `purpose()`/`validationRules()` overrides (ordinary server-side PHP, never trusting anything
+  the request itself claims about its own limits) — a real policy decision that can differ per
+  site and even per product/field, not something a shared base class or config file could
+  express safely.
+- `boboko:file:prune-unowned {purpose}` — deletes every unowned `File` of a given purpose past
+  its grace period (`--hours`, default 24). Generic: any consuming app schedules it once per
+  purpose string it stores files under.
+- `Modules\Core\Cart\Events\CartLineAdded`/`Checkout\Events\OrderPlaced` listeners
+  (`File\Listeners\AttachCustomFieldFileToCartLine`/`TransferCustomFieldFileOwnership`) that
+  re-point a `File`'s ownership from unowned → the real `CartLine` once one exists, then from
+  that `CartLine` → the `OrderLine` an order is placed with — so a File referenced by a product
+  custom field survives the cart it originated from being cleared, without ever being copied.
+
+### Changed
+- The admin order-lines table's collapsible details dropdown (next to the existing price
+  breakdown) now shows a product's custom-field answers (`OrderLine.meta.custom_fields`) — a
+  bordered table matching the existing price-breakdown one, with a thumbnail preview and a
+  download-icon link for a file answer, resolved through `File\Services\FileService`'s signed
+  route. Previously never shown anywhere in the admin.
+- 3dealer's product custom-field photo upload (`CustomFieldUploadController`), cart line meta
+  (`CartController::customFieldsMeta()`), and pruning (formerly its own `PruneCustomFieldUploads`
+  command) now go through `Modules\Core\File` instead of a bespoke `Crypt::encryptString({disk,
+  path, name, mime})` reference scheme — a cart/order line's file answer is now just a `File`
+  row's `file_id`, with `File` as the single source of truth for every other detail.
+
 ## [0.20.2] - 2026-09-25
 
 ### Changed
diff --git a/composer.json b/composer.json
index 931c13d..234757a 100644
--- a/composer.json
+++ b/composer.json
@@ -2,7 +2,7 @@
   "name": "boboko/core",
   "description": "Core module — authentication and shared panel behaviour",
   "type": "library",
-  "version": "0.20.2",
+  "version": "0.21.0",
   "autoload": {
     "psr-4": {
       "Modules\\Core\\": "src/"