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+# Feed Detail Route Groups Architecture
+
+## Motivation
+Previously, feed detail routes used a proxy rewrite pattern:
+- The proxy intercepted `/feeds/:feedDataType/:feedId` and rewrote it internally to `/feeds/:feedDataType/:feedId/authed` or `/feeds/:feedDataType/:feedId/static`.
+- The `authed` and `static` route folders relied on custom HTTP header guards (`x-mdb-authed-proxy`, `x-mdb-static-proxy`) and called `notFound()` if accessed directly.
+
+## Solution: Next.js Route Groups
+Using route groups `(authed)` and `(static)` inside `src/app/[locale]/feeds/[feedDataType]/[feedId]`:
+- URL paths remain clean and canonical: `/feeds/:feedDataType/:feedId` without exposing `/authed` or `/static` in URL segments.
+- `(static)`: Leverages Next.js SSG / ISR for search engines and public visitors.
+- `(authed)`: Serves authenticated users with personalized features (subscriptions, custom actions) using dynamic server rendering.
+- Eliminates header guard vulnerabilities and simplifies the proxy routing middleware.