diff --git a/web/src/build.ts b/web/src/build.ts
index 83e273f..1a9bd95 100644
--- a/web/src/build.ts
+++ b/web/src/build.ts
@@ -10,6 +10,7 @@ const __dirname = dirname(fileURLToPath(import.meta.url))
 const sitesDir = join(__dirname, 'sites')
 const contentDir = join(__dirname, 'content/pages')
 const assetsDir = join(__dirname, 'assets')
+const wellKnownDir = join(__dirname, 'well-known')
 const distDir = join(__dirname, '..', 'dist')
 
 // Load all site configs
@@ -100,6 +101,14 @@ function buildSite(site: SiteConfig, pages: ReturnType<typeof loadPages>): void
   writeFileSync(metadataPath, clientMetadata(site))
   console.log(`  -> .well-known/client-metadata.json`)
 
+  // Copy apple-app-site-association for Universal Links
+  const aasaSource = join(wellKnownDir, 'apple-app-site-association')
+  if (existsSync(aasaSource)) {
+    const aasaPath = join(siteDir, '.well-known/apple-app-site-association')
+    copyFileSync(aasaSource, aasaPath)
+    console.log(`  -> .well-known/apple-app-site-association`)
+  }
+
   // Copy assets
   copyAssets(site)
 }
diff --git a/web/src/well-known/apple-app-site-association b/web/src/well-known/apple-app-site-association
new file mode 100644
index 0000000..2b37983
--- /dev/null
+++ b/web/src/well-known/apple-app-site-association
@@ -0,0 +1,14 @@
+{
+  "applinks": {
+    "apps": [],
+    "details": [
+      {
+        "appID": "WN6KD5ZT49.ai.syui.card",
+        "paths": [
+          "/oauth/callback",
+          "/oauth/callback/"
+        ]
+      }
+    ]
+  }
+}