diff --git a/src/lib/microcosm/hydrate.ts b/src/lib/microcosm/hydrate.ts
index 52a9c4d..4f2a6ca 100644
--- a/src/lib/microcosm/hydrate.ts
+++ b/src/lib/microcosm/hydrate.ts
@@ -117,11 +117,33 @@ type RawImage = {
   alt?: string
   aspectRatio?: {width: number; height: number}
 }
+type StrongRef = {uri: string; cid?: string}
 type RawExternal = {
   uri?: string
   title?: string
   description?: string
   thumb?: unknown
+  /**
+   * StrongRefs to the atproto records backing this link (e.g. a
+   * site.standard.publication / site.standard.document). Written into the post
+   * record by the author; the AppView surfaces them as `associatedRefs` and uses
+   * them to render the rich Standard publication card.
+   */
+  associatedRefs?: StrongRef[]
+}
+
+type RgbColor = {r?: number; g?: number; b?: number}
+type StandardTheme = {
+  primary?: RgbColor
+  accentText?: RgbColor
+  backgroundColor?: RgbColor
+  pageBackground?: RgbColor
+}
+type StandardPublicationRecord = {
+  url?: string
+  name?: string
+  icon?: unknown
+  theme?: StandardTheme
 }
 
 function hydrateImagesView(did: string, e: {images?: unknown}): unknown {
@@ -139,9 +161,64 @@ function hydrateImagesView(did: string, e: {images?: unknown}): unknown {
   }
 }
 
-function hydrateExternalView(did: string, e: {external?: unknown}): unknown {
+function rgb(c: RgbColor | undefined) {
+  if (!c || c.r == null || c.g == null || c.b == null) return undefined
+  return {$type: 'app.bsky.embed.external#colorRGB', r: c.r, g: c.g, b: c.b}
+}
+
+/**
+ * Build the rich `source` for a Standard publication embed. The post record's
+ * external `associatedRefs` point at the backing `site.standard.publication`
+ * record; we fetch it for the publication url/title/icon/theme. Returns
+ * undefined for non-Standard embeds or if the publication can't be fetched.
+ */
+async function hydrateStandardSource(
+  associatedRefs: StrongRef[] | undefined,
+  signal?: AbortSignal,
+): Promise<Record<string, unknown> | undefined> {
+  const pubRef = associatedRefs?.find(
+    r => parseAtUri(r.uri)?.collection === 'site.standard.publication',
+  )
+  if (!pubRef) return undefined
+  const parsed = parseAtUri(pubRef.uri)
+  if (!parsed) return undefined
+
+  const rec = await getRecordByUri(pubRef.uri, undefined, signal).catch(
+    () => undefined,
+  )
+  if (!rec) return undefined
+  const pub = rec.value as StandardPublicationRecord
+
+  const accentRGB = rgb(pub.theme?.primary)
+  const accentForegroundRGB = rgb(pub.theme?.accentText)
+  return {
+    $type: 'app.bsky.embed.external#viewExternalSource',
+    uri: pub.url ?? '',
+    title: pub.name ?? '',
+    icon: cdnUrl('avatar', parsed.did, pub.icon),
+    theme:
+      accentRGB || accentForegroundRGB
+        ? {
+            $type: 'app.bsky.embed.external#viewExternalSourceTheme',
+            accentRGB,
+            accentForegroundRGB,
+            backgroundRGB: rgb(pub.theme?.backgroundColor),
+            foregroundRGB: rgb(pub.theme?.pageBackground),
+          }
+        : undefined,
+  }
+}
+
+async function hydrateExternalView(
+  did: string,
+  e: {external?: unknown},
+  signal?: AbortSignal,
+): Promise<unknown> {
   const ext = e.external as RawExternal | undefined
   if (!ext) return undefined
+  const source = await hydrateStandardSource(ext.associatedRefs, signal).catch(
+    () => undefined,
+  )
   return {
     $type: 'app.bsky.embed.external#view',
     external: {
@@ -149,6 +226,12 @@ function hydrateExternalView(did: string, e: {external?: unknown}): unknown {
       title: ext.title ?? '',
       description: ext.description ?? '',
       thumb: cdnUrl('feed_thumbnail', did, ext.thumb),
+      associatedRefs: ext.associatedRefs?.map(r => ({
+        $type: 'com.atproto.repo.strongRef',
+        uri: r.uri,
+        cid: r.cid,
+      })),
+      source,
     },
   }
 }
@@ -193,7 +276,7 @@ async function hydrateEmbed(
   }
 
   if (e.$type === 'app.bsky.embed.external') {
-    return hydrateExternalView(did, e)
+    return hydrateExternalView(did, e, signal)
   }
 
   if (e.$type === 'app.bsky.embed.record') {
@@ -219,13 +302,11 @@ async function hydrateEmbed(
             .then(p => (p ? quotedPostToViewRecord(p) : undefined))
             .catch(() => undefined)
         : Promise.resolve(undefined),
-      Promise.resolve(
-        media?.$type === 'app.bsky.embed.images'
-          ? hydrateImagesView(did, media as {images?: unknown})
-          : media?.$type === 'app.bsky.embed.external'
-            ? hydrateExternalView(did, media as {external?: unknown})
-            : undefined,
-      ),
+      media?.$type === 'app.bsky.embed.images'
+        ? Promise.resolve(hydrateImagesView(did, media as {images?: unknown}))
+        : media?.$type === 'app.bsky.embed.external'
+          ? hydrateExternalView(did, media as {external?: unknown}, signal)
+          : Promise.resolve(undefined),
     ])
     if (!recordView && !mediaView) return undefined
     return {