diff --git a/src/lib/components/RustyImage.svelte b/src/lib/components/RustyImage.svelte
index f041eb1..bdeb5b0 100644
--- a/src/lib/components/RustyImage.svelte
+++ b/src/lib/components/RustyImage.svelte
@@ -37,6 +37,8 @@
     /** JPEG/AVIF/WebP-Qualität. Default 75. */
     quality?: number;
     fit?: "cover" | "contain" | "fill";
+    /** Cache-Bust-Tag (z.B. post._updated) → `_v`-Param, bricht Browser-HTTP-Cache. */
+    version?: string;
   }
 
   let {
@@ -56,6 +58,7 @@
     formats = ["webp", "jpeg"],
     quality = 75,
     fit = "cover",
+    version,
   }: Props = $props();
 
   function parseAr(s: string | undefined): number | null {
@@ -89,6 +92,7 @@
       ...(arString && fit !== "contain"
         ? { height: Math.round(w / (arValue ?? 1)) }
         : {}),
+      ...(version ? { version } : {}),
     };
   }
 
diff --git a/src/lib/rusty-image.ts b/src/lib/rusty-image.ts
index f374b8a..5e84e0b 100644
--- a/src/lib/rusty-image.ts
+++ b/src/lib/rusty-image.ts
@@ -68,6 +68,13 @@ export interface RustyImageTransformParams {
   focalX?: number;
   /** Focal-Y in [0,1] (Default 0.5). */
   focalY?: number;
+  /**
+   * Cache-busting tag (e.g. post._updated). Serialized as `_v` and is the
+   * only param the cms-images endpoint deliberately ignores when forwarding
+   * to RustyCMS — its sole job is to invalidate the browser HTTP cache when
+   * the underlying entry (focal, alt, replacement) changes.
+   */
+  version?: string;
 }
 
 function roundFocal(v: number): number {
@@ -89,6 +96,7 @@ export function getCmsImageUrl(src: string, params: RustyImageTransformParams =
   if (params.quality != null) searchParams.set('q', String(params.quality));
   if (params.focalX != null) searchParams.set('fx', String(roundFocal(params.focalX)));
   if (params.focalY != null) searchParams.set('fy', String(roundFocal(params.focalY)));
+  if (params.version) searchParams.set('_v', params.version);
   return `/cms-images?${searchParams.toString()}`;
 }
 
diff --git a/src/routes/post/[slug]/+page.svelte b/src/routes/post/[slug]/+page.svelte
index ee2e0f4..b13fbe1 100644
--- a/src/routes/post/[slug]/+page.svelte
+++ b/src/routes/post/[slug]/+page.svelte
@@ -45,6 +45,7 @@
         class="block object-cover"
         loading="eager"
         fetchpriority="high"
+        version={(data.post as { _updated?: string })._updated?.slice(0, 19)}
       />
     </div>
   {:else if data.postImageUrl}