From dc7eb77fad6ecd37862276d6104ada6b996667c5 Mon Sep 17 00:00:00 2001
From: xfy <i@rua.plus>
Date: Wed, 17 Jun 2026 14:19:42 +0800
Subject: [PATCH] docs: document image cache-control defaults

---
 .env.example | 5 +++++
 1 file changed, 5 insertions(+)

diff --git a/.env.example b/.env.example
index fdfbf9f..d97cbf5 100644
--- a/.env.example
+++ b/.env.example
@@ -25,3 +25,8 @@ DB_POOL_SIZE=20
 
 # SSR page cache duration in seconds (default: 3600)
 SSR_CACHE_SECS=3600
+
+# Image serving cache headers
+# Uploaded image assets are served with Cache-Control: public, max-age=31536000, immutable.
+# Processed variants (?w=, ?format=, etc.) are cached for 24 hours.
+# To force browsers to refresh, change the URL or restart the server.