diff --git a/package-lock.json b/package-lock.json
index 3f84098..929b000 100644
--- a/package-lock.json
+++ b/package-lock.json
@@ -16,7 +16,8 @@
         "lucide-react": "^0.460.0",
         "next": "16.2.6",
         "react": "19.2.4",
-        "react-dom": "19.2.4"
+        "react-dom": "19.2.4",
+        "sonner": "^2.0.7"
       },
       "devDependencies": {
         "@biomejs/biome": "^2.5.0",
diff --git a/package.json b/package.json
index b8cde33..8c9ee43 100644
--- a/package.json
+++ b/package.json
@@ -24,7 +24,8 @@
     "lucide-react": "^0.460.0",
     "next": "16.2.6",
     "react": "19.2.4",
-    "react-dom": "19.2.4"
+    "react-dom": "19.2.4",
+    "sonner": "^2.0.7"
   },
   "devDependencies": {
     "@biomejs/biome": "^2.5.0",
diff --git a/src/app/layout.tsx b/src/app/layout.tsx
index 7953118..b785948 100644
--- a/src/app/layout.tsx
+++ b/src/app/layout.tsx
@@ -1,4 +1,4 @@
-import { Button, ThemeProvider } from "@mind-studio/ui";
+import { Button, ThemeProvider, Toaster } from "@mind-studio/ui";
 import { mind } from "@mind-studio/ui/themes";
 import type { Metadata } from "next";
 import { Fraunces, Hanken_Grotesk, JetBrains_Mono } from "next/font/google";
@@ -56,6 +56,7 @@ export default function RootLayout({ children }: Readonly<{ children: React.Reac
             <Colophon />
             <FeedbackLauncher />
           </StandaloneOnly>
+          <Toaster position="bottom-right" />
         </ThemeProvider>
       </body>
     </html>
diff --git a/src/components/DriveBrowser.tsx b/src/components/DriveBrowser.tsx
index 1ebc8af..56465fc 100644
--- a/src/components/DriveBrowser.tsx
+++ b/src/components/DriveBrowser.tsx
@@ -15,6 +15,7 @@ import {
 import Link from "next/link";
 import { useRouter } from "next/navigation";
 import { useCallback, useEffect, useMemo, useRef, useState } from "react";
+import { toast } from "sonner";
 import { ConfirmDialog } from "@/components/ConfirmDialog";
 import PassphraseDialog from "@/components/PassphraseDialog";
 import { ImageThumbnail, isImageName } from "@/components/Thumbnail";
@@ -462,7 +463,7 @@ function Toolbar({
       setCreatingFolder(false);
       onChanged();
     } catch (err) {
-      alert(`Failed to create folder: ${String(err)}`);
+      toast.error(`Failed to create folder: ${String(err)}`);
     } finally {
       setBusy(false);
     }
@@ -725,7 +726,7 @@ function Tile({
       }
       onChanged();
     } catch (err) {
-      alert(`Delete failed: ${String(err)}`);
+      toast.error(`Delete failed: ${String(err)}`);
     } finally {
       setBusy(false);
     }
@@ -822,7 +823,7 @@ function Row({
       }
       onChanged();
     } catch (err) {
-      alert(`Delete failed: ${String(err)}`);
+      toast.error(`Delete failed: ${String(err)}`);
     } finally {
       setBusy(false);
     }
@@ -843,7 +844,7 @@ function Row({
       a.remove();
       setTimeout(() => URL.revokeObjectURL(url), 1000);
     } catch (err) {
-      alert(`Download failed: ${String(err)}`);
+      toast.error(`Download failed: ${String(err)}`);
     } finally {
       setBusy(false);
     }
@@ -858,7 +859,7 @@ function Row({
       return;
     }
     if (entry.kind === "container") {
-      alert("Container rename is not supported in M2 — copy/recreate manually.");
+      toast.error("Container rename is not supported in M2 — copy/recreate manually.");
       setRenaming(false);
       return;
     }
@@ -870,7 +871,7 @@ function Row({
       setRenaming(false);
       onChanged();
     } catch (err) {
-      alert(`Rename failed: ${String(err)}`);
+      toast.error(`Rename failed: ${String(err)}`);
     } finally {
       setBusy(false);
     }
diff --git a/src/components/FilePreview.tsx b/src/components/FilePreview.tsx
index 06a3efa..81cc4be 100644
--- a/src/components/FilePreview.tsx
+++ b/src/components/FilePreview.tsx
@@ -5,6 +5,7 @@ import { ArrowLeft, Download, Pencil, Share2, Trash2 } from "lucide-react";
 import Link from "next/link";
 import { useRouter } from "next/navigation";
 import { useCallback, useEffect, useMemo, useState } from "react";
+import { toast } from "sonner";
 import { ConfirmDialog } from "@/components/ConfirmDialog";
 import PassphraseDialog from "@/components/PassphraseDialog";
 import ShareDialog from "@/components/ShareDialog";
@@ -299,7 +300,7 @@ function Header({
           : "/drive/" + parentSegments.map(normalizeSegment).join("/");
       router.replace(parentHref);
     } catch (e) {
-      alert(`Delete failed: ${String(e)}`);
+      toast.error(`Delete failed: ${String(e)}`);
       setBusy(false);
     }
   }
@@ -323,7 +324,7 @@ function Header({
         [...parentSegments.map(normalizeSegment), encodeURIComponent(trimmed)].join("/");
       router.replace(href);
     } catch (err) {
-      alert(`Rename failed: ${String(err)}`);
+      toast.error(`Rename failed: ${String(err)}`);
       setBusy(false);
     }
   }