diff --git a/ui/src/routes/discover/+page.svelte b/ui/src/routes/discover/+page.svelte
index 935be27..342c7f6 100644
--- a/ui/src/routes/discover/+page.svelte
+++ b/ui/src/routes/discover/+page.svelte
@@ -239,6 +239,16 @@
 			body: JSON.stringify({ slug: book.slug, action })
 		});
 
+		// Optimistically add/update the history list so the drawer shows it immediately.
+		// If this slug was already voted (e.g. swiped twice via undo+re-swipe), replace it.
+		const existing = votedBooks.findIndex((v) => v.slug === book.slug);
+		const entry: VotedBook = { slug: book.slug, action, votedAt: new Date().toISOString(), book };
+		if (existing !== -1) {
+			votedBooks = [entry, ...votedBooks.filter((_, i) => i !== existing)];
+		} else {
+			votedBooks = [entry, ...votedBooks];
+		}
+
 		// Fly out
 		transitioning = true;
 		const target = flyTargets[action];