diff --git a/integrations/island/package.json b/integrations/island/package.json
index a4a07108..c0262fe1 100644
--- a/integrations/island/package.json
+++ b/integrations/island/package.json
@@ -24,7 +24,7 @@
     "magic-string": "^0.30.5",
     "magic-string-stack": "^1.0.0",
     "stack54": "workspace:^",
-    "svelte": "^4.2.8",
+    "svelte": "^5.0.0",
     "ts-dedent": "^2.2.0",
     "vite": "^7.0.0"
   },
diff --git a/integrations/streaming/package.json b/integrations/streaming/package.json
index 49071069..1c2bf5d5 100644
--- a/integrations/streaming/package.json
+++ b/integrations/streaming/package.json
@@ -39,11 +39,11 @@
   ],
   "devDependencies": {
     "@types/node": "^24.0.0",
-    "svelte": "4.2.20",
+    "svelte": "5.51.5",
     "typescript": "^5.3.3",
     "vitest": "^4.0.17"
   },
   "peerDependencies": {
-    "svelte": "4.2.20"
+    "svelte": "5.51.5"
   }
 }
diff --git a/packages/core/package.json b/packages/core/package.json
index 6330dcb6..f9c5fb81 100644
--- a/packages/core/package.json
+++ b/packages/core/package.json
@@ -47,7 +47,7 @@
     "@types/fs-extra": "^11.0.4",
     "@types/node": "^24.0.0",
     "@types/picomatch": "^4.0.0",
-    "svelte": "^4.2.8",
+    "svelte": "^5.0.0",
     "typescript": "^5.3.3",
     "vite": "^7.0.0",
     "vitest": "^4.0.16"
diff --git a/pnpm-lock.yaml b/pnpm-lock.yaml
index dfbe0d74..7a70966a 100644
--- a/pnpm-lock.yaml
+++ b/pnpm-lock.yaml
@@ -308,8 +308,8 @@ importers:
         specifier: workspace:^
         version: link:../../packages/core
       svelte:
-        specifier: ^4.2.8
-        version: 4.2.20
+        specifier: ^5.0.0
+        version: 5.51.5
       ts-dedent:
         specifier: ^2.2.0
         version: 2.2.0
@@ -371,8 +371,8 @@ importers:
         specifier: ^24.0.0
         version: 24.12.2
       svelte:
-        specifier: 4.2.20
-        version: 4.2.20
+        specifier: 5.51.5
+        version: 5.51.5
       typescript:
         specifier: ^5.3.3
         version: 5.9.3
@@ -485,7 +485,7 @@ importers:
         version: 2.30.0(@types/node@24.12.2)
       '@sveltejs/vite-plugin-svelte':
         specifier: ^3.0.1
-        version: 3.1.2(svelte@4.2.20)(vite@7.3.1(@types/node@24.12.2)(jiti@2.6.1)(lightningcss@1.32.0)(terser@5.46.1)(tsx@4.21.0)(yaml@2.8.3))
+        version: 3.1.2(svelte@5.51.5)(vite@7.3.1(@types/node@24.12.2)(jiti@2.6.1)(lightningcss@1.32.0)(terser@5.46.1)(tsx@4.21.0)(yaml@2.8.3))
       '@types/cookie':
         specifier: ^0.6.0
         version: 0.6.0
@@ -499,8 +499,8 @@ importers:
         specifier: ^4.0.0
         version: 4.0.2
       svelte:
-        specifier: ^4.2.8
-        version: 4.2.20
+        specifier: ^5.0.0
+        version: 5.51.5
       typescript:
         specifier: ^5.3.3
         version: 5.9.3
@@ -1529,6 +1529,11 @@ packages:
   '@standard-schema/spec@1.1.0':
     resolution: {integrity: sha512-l2aFy5jALhniG5HgqrD6jXLi/rUWrKvqN/qJx6yoJsgKhblVd+iqqU4RCXavm/jPityDo5TCvKMnpjKnOriy0w==}
 
+  '@sveltejs/acorn-typescript@1.0.9':
+    resolution: {integrity: sha512-lVJX6qEgs/4DOcRTpo56tmKzVPtoWAaVbL4hfO7t7NVwl9AAXzQR6cihesW1BmNMPl+bK6dreu2sOKBP2Q9CIA==}
+    peerDependencies:
+      acorn: ^8.9.0
+
   '@sveltejs/vite-plugin-svelte-inspector@2.1.0':
     resolution: {integrity: sha512-9QX28IymvBlSCqsCll5t0kQVxipsfhFFL+L2t3nTWfXnddYwxBuAEtTtlaVQpRz9c37BhJjltSeY4AJSC03SSg==}
     engines: {node: ^18.0.0 || >=20}
@@ -1622,6 +1627,9 @@ packages:
   '@types/set-cookie-parser@2.4.10':
     resolution: {integrity: sha512-GGmQVGpQWUe5qglJozEjZV/5dyxbOOZ0LHe/lqyWssB88Y4svNfst0uqBVscdDeIKl5Jy5+aPSvy7mI9tYRguw==}
 
+  '@types/trusted-types@2.0.7':
+    resolution: {integrity: sha512-ScaPdn1dQczgbl0QFTeTOmVHFULt394XJgOQNoyVhZ6r2vLnMLJfBPd53SB52T/3G36VI1/g2MZaX0cwDuXsfw==}
+
   '@types/yargs-parser@21.0.3':
     resolution: {integrity: sha512-I4q9QU9MQv4oEOz4tAHJtNz1cwuLxn2F3xcc2iV5WdqLPpUnj30aUuxt1mAxYTG+oe8CZMV/+6rU4S4gRDzqtQ==}
 
@@ -1815,6 +1823,10 @@ packages:
     resolution: {integrity: sha512-k7ndgKhwoQveBL+/1tqGJYNz097I7WOvwbmmU2AR5+magtbjPWQTS1C5vzGkBC8Ym8UWRzfKUzUUqFLypY4Q+w==}
     engines: {node: '>=20'}
 
+  clsx@2.1.1:
+    resolution: {integrity: sha512-eYm0QWBtUrBWZWG0d386OGAw16Z995PiOVo2B7bjWSbHedGl5e0ZWaq65kOGgUSNesEIDkB9ISbTg/JK9dhCZA==}
+    engines: {node: '>=6'}
+
   code-red@1.0.4:
     resolution: {integrity: sha512-7qJWqItLA8/VPVlKJlFXU+NBlo/qyfs39aJcuMT/2ere32ZqvF5OSxgdM5xOfJJ7O429gg2HM47y8v9P+9wrNw==}
 
@@ -2028,11 +2040,22 @@ packages:
   escape-html@1.0.3:
     resolution: {integrity: sha512-NiSupZ4OeuGwr68lGIeym/ksIZMJodUGOSCZ/FSnTxcrekbvqrgdUxlJOMpijaKZVjAJrWrGs/6Jy8OMuyj9ow==}
 
+  esm-env@1.2.2:
+    resolution: {integrity: sha512-Epxrv+Nr/CaL4ZcFGPJIYLWFom+YeV1DqMLHJoEd9SYRxNbaFruBwfEX/kkHUJf55j2+TUbmDcmuilbP1TmXHA==}
+
   esprima@4.0.1:
     resolution: {integrity: sha512-eGuFFw7Upda+g4p+QHvnW0RyTX/SVeJBDM/gCtMARO0cLuT2HcEKnTPvhjV6aGeqrCB/sbNop0Kszm0jsaWU4A==}
     engines: {node: '>=4'}
     hasBin: true
 
+  esrap@2.2.5:
+    resolution: {integrity: sha512-/yLB1538mag+dn0wsePTe8C0rDIjUOaJpMs2McodSzmM2msWcZsBSdRtg6HOBt0A/r82BN+Md3pgwSc/uWt2Ig==}
+    peerDependencies:
+      '@typescript-eslint/types': ^8.2.0
+    peerDependenciesMeta:
+      '@typescript-eslint/types':
+        optional: true
+
   estree-walker@3.0.3:
     resolution: {integrity: sha512-7RUKfXgSMMkzt6ZuXmqapOurLGPPfgj6l9uRZ7lRGolvk0y2yocc35LdcxKC5PQZdn2DMqioAQ2NoWcrTKmm6g==}
 
@@ -2943,6 +2966,10 @@ packages:
     resolution: {integrity: sha512-eeEgGc2DtiUil5ANdtd8vPwt9AgaMdnuUFnPft9F5oMvU/FHu5IHFic+p1dR/UOB7XU2mX2yHW+NcTch4DCh5Q==}
     engines: {node: '>=16'}
 
+  svelte@5.51.5:
+    resolution: {integrity: sha512-/4tR5cLsWOgH3wnNRXnFoWaJlwPGbJanZPSKSD6nHM2y01dvXeEF4Nx7jevoZ+UpJpkIHh6mY2tqDncuI4GHng==}
+    engines: {node: '>=18'}
+
   symbol-tree@3.2.4:
     resolution: {integrity: sha512-9QNk5KwDF+Bvz+PyObkmSYjI5ksVUYtjW7AU22r2NKcfLJcXp96hkDWU3+XndOsUb+AQ9QhfzfCT2O+CNWT5Tw==}
 
@@ -3263,6 +3290,9 @@ packages:
     resolution: {integrity: sha512-CzhO+pFNo8ajLM2d2IW/R93ipy99LWjtwblvC1RsoSUMZgyLbYFr221TnSNT7GjGdYui6P459mw9JH/g/zW2ug==}
     engines: {node: '>=18'}
 
+  zimmerframe@1.1.4:
+    resolution: {integrity: sha512-B58NGBEoc8Y9MWWCQGl/gq9xBCe4IiKM0a2x7GZdQKOW5Exr8S1W24J6OgM1njK8xCRGvAJIL/MxXHf6SkmQKQ==}
+
   zod@3.25.76:
     resolution: {integrity: sha512-gzUt/qt81nXsFGKIFcC3YnfEAx5NkunCfnDlvuBSSFS02bcXu4Lmea0AFIUwbLWxWPx3d9p8S5QoaujKcNQxcQ==}
 
@@ -4073,6 +4103,10 @@ snapshots:
 
   '@standard-schema/spec@1.1.0': {}
 
+  '@sveltejs/acorn-typescript@1.0.9(acorn@8.16.0)':
+    dependencies:
+      acorn: 8.16.0
+
   '@sveltejs/vite-plugin-svelte-inspector@2.1.0(@sveltejs/vite-plugin-svelte@3.1.2(svelte@4.2.20)(vite@5.4.21(@types/node@25.6.0)(lightningcss@1.32.0)(terser@5.46.1)))(svelte@4.2.20)(vite@5.4.21(@types/node@25.6.0)(lightningcss@1.32.0)(terser@5.46.1))':
     dependencies:
       '@sveltejs/vite-plugin-svelte': 3.1.2(svelte@4.2.20)(vite@5.4.21(@types/node@25.6.0)(lightningcss@1.32.0)(terser@5.46.1))
@@ -4082,11 +4116,11 @@ snapshots:
     transitivePeerDependencies:
       - supports-color
 
-  '@sveltejs/vite-plugin-svelte-inspector@2.1.0(@sveltejs/vite-plugin-svelte@3.1.2(svelte@4.2.20)(vite@7.3.1(@types/node@24.12.2)(jiti@2.6.1)(lightningcss@1.32.0)(terser@5.46.1)(tsx@4.21.0)(yaml@2.8.3)))(svelte@4.2.20)(vite@7.3.1(@types/node@24.12.2)(jiti@2.6.1)(lightningcss@1.32.0)(terser@5.46.1)(tsx@4.21.0)(yaml@2.8.3))':
+  '@sveltejs/vite-plugin-svelte-inspector@2.1.0(@sveltejs/vite-plugin-svelte@3.1.2(svelte@5.51.5)(vite@7.3.1(@types/node@24.12.2)(jiti@2.6.1)(lightningcss@1.32.0)(terser@5.46.1)(tsx@4.21.0)(yaml@2.8.3)))(svelte@5.51.5)(vite@7.3.1(@types/node@24.12.2)(jiti@2.6.1)(lightningcss@1.32.0)(terser@5.46.1)(tsx@4.21.0)(yaml@2.8.3))':
     dependencies:
-      '@sveltejs/vite-plugin-svelte': 3.1.2(svelte@4.2.20)(vite@7.3.1(@types/node@24.12.2)(jiti@2.6.1)(lightningcss@1.32.0)(terser@5.46.1)(tsx@4.21.0)(yaml@2.8.3))
+      '@sveltejs/vite-plugin-svelte': 3.1.2(svelte@5.51.5)(vite@7.3.1(@types/node@24.12.2)(jiti@2.6.1)(lightningcss@1.32.0)(terser@5.46.1)(tsx@4.21.0)(yaml@2.8.3))
       debug: 4.4.3
-      svelte: 4.2.20
+      svelte: 5.51.5
       vite: 7.3.1(@types/node@24.12.2)(jiti@2.6.1)(lightningcss@1.32.0)(terser@5.46.1)(tsx@4.21.0)(yaml@2.8.3)
     transitivePeerDependencies:
       - supports-color
@@ -4105,15 +4139,15 @@ snapshots:
     transitivePeerDependencies:
       - supports-color
 
-  '@sveltejs/vite-plugin-svelte@3.1.2(svelte@4.2.20)(vite@7.3.1(@types/node@24.12.2)(jiti@2.6.1)(lightningcss@1.32.0)(terser@5.46.1)(tsx@4.21.0)(yaml@2.8.3))':
+  '@sveltejs/vite-plugin-svelte@3.1.2(svelte@5.51.5)(vite@7.3.1(@types/node@24.12.2)(jiti@2.6.1)(lightningcss@1.32.0)(terser@5.46.1)(tsx@4.21.0)(yaml@2.8.3))':
     dependencies:
-      '@sveltejs/vite-plugin-svelte-inspector': 2.1.0(@sveltejs/vite-plugin-svelte@3.1.2(svelte@4.2.20)(vite@7.3.1(@types/node@24.12.2)(jiti@2.6.1)(lightningcss@1.32.0)(terser@5.46.1)(tsx@4.21.0)(yaml@2.8.3)))(svelte@4.2.20)(vite@7.3.1(@types/node@24.12.2)(jiti@2.6.1)(lightningcss@1.32.0)(terser@5.46.1)(tsx@4.21.0)(yaml@2.8.3))
+      '@sveltejs/vite-plugin-svelte-inspector': 2.1.0(@sveltejs/vite-plugin-svelte@3.1.2(svelte@5.51.5)(vite@7.3.1(@types/node@24.12.2)(jiti@2.6.1)(lightningcss@1.32.0)(terser@5.46.1)(tsx@4.21.0)(yaml@2.8.3)))(svelte@5.51.5)(vite@7.3.1(@types/node@24.12.2)(jiti@2.6.1)(lightningcss@1.32.0)(terser@5.46.1)(tsx@4.21.0)(yaml@2.8.3))
       debug: 4.4.3
       deepmerge: 4.3.1
       kleur: 4.1.5
       magic-string: 0.30.21
-      svelte: 4.2.20
-      svelte-hmr: 0.16.0(svelte@4.2.20)
+      svelte: 5.51.5
+      svelte-hmr: 0.16.0(svelte@5.51.5)
       vite: 7.3.1(@types/node@24.12.2)(jiti@2.6.1)(lightningcss@1.32.0)(terser@5.46.1)(tsx@4.21.0)(yaml@2.8.3)
       vitefu: 0.2.5(vite@7.3.1(@types/node@24.12.2)(jiti@2.6.1)(lightningcss@1.32.0)(terser@5.46.1)(tsx@4.21.0)(yaml@2.8.3))
     transitivePeerDependencies:
@@ -4221,6 +4255,8 @@ snapshots:
     dependencies:
       '@types/node': 24.12.2
 
+  '@types/trusted-types@2.0.7': {}
+
   '@types/yargs-parser@21.0.3': {}
 
   '@types/yargs@17.0.35':
@@ -4442,6 +4478,8 @@ snapshots:
       strip-ansi: 7.2.0
       wrap-ansi: 9.0.2
 
+  clsx@2.1.1: {}
+
   code-red@1.0.4:
     dependencies:
       '@jridgewell/sourcemap-codec': 1.5.5
@@ -4703,8 +4741,14 @@ snapshots:
 
   escape-html@1.0.3: {}
 
+  esm-env@1.2.2: {}
+
   esprima@4.0.1: {}
 
+  esrap@2.2.5:
+    dependencies:
+      '@jridgewell/sourcemap-codec': 1.5.5
+
   estree-walker@3.0.3:
     dependencies:
       '@types/estree': 1.0.8
@@ -5692,6 +5736,10 @@ snapshots:
     dependencies:
       svelte: 4.2.20
 
+  svelte-hmr@0.16.0(svelte@5.51.5):
+    dependencies:
+      svelte: 5.51.5
+
   svelte@4.2.20:
     dependencies:
       '@ampproject/remapping': 2.3.0
@@ -5709,6 +5757,27 @@ snapshots:
       magic-string: 0.30.21
       periscopic: 3.1.0
 
+  svelte@5.51.5:
+    dependencies:
+      '@jridgewell/remapping': 2.3.5
+      '@jridgewell/sourcemap-codec': 1.5.5
+      '@sveltejs/acorn-typescript': 1.0.9(acorn@8.16.0)
+      '@types/estree': 1.0.8
+      '@types/trusted-types': 2.0.7
+      acorn: 8.16.0
+      aria-query: 5.3.2
+      axobject-query: 4.1.0
+      clsx: 2.1.1
+      devalue: 5.6.4
+      esm-env: 1.2.2
+      esrap: 2.2.5
+      is-reference: 3.0.3
+      locate-character: 3.0.0
+      magic-string: 0.30.21
+      zimmerframe: 1.1.4
+    transitivePeerDependencies:
+      - '@typescript-eslint/types'
+
   symbol-tree@3.2.4:
     optional: true
 
@@ -6026,4 +6095,6 @@ snapshots:
 
   yoctocolors@2.1.2: {}
 
+  zimmerframe@1.1.4: {}
+
   zod@3.25.76: {}
diff --git a/templates/express/package.json b/templates/express/package.json
index f930205f..dcfb4f05 100644
--- a/templates/express/package.json
+++ b/templates/express/package.json
@@ -23,7 +23,7 @@
     "method-override": "^3.0.0",
     "morgan": "^1.10.0",
     "stack54": "^0.14.0",
-    "svelte": "^4.2.8"
+    "svelte": "^5.51.5"
   },
   "devDependencies": {
     "@playwright/test": "^1.46.1",
diff --git a/templates/hono/package.json b/templates/hono/package.json
index 9af917d2..d84666e2 100644
--- a/templates/hono/package.json
+++ b/templates/hono/package.json
@@ -16,7 +16,7 @@
     "@hono/vite-dev-server": "^0.24.0",
     "hono": "^4.10.6",
     "stack54": "^0.14.0",
-    "svelte": "^4.2.8"
+    "svelte": "^5.51.5"
   },
   "devDependencies": {
     "@sveltejs/vite-plugin-svelte": "^3.0.1",
diff --git a/templates/htmx/package.json b/templates/htmx/package.json
index 18a1a1f0..35f3f1cc 100644
--- a/templates/htmx/package.json
+++ b/templates/htmx/package.json
@@ -24,7 +24,7 @@
     "method-override": "^3.0.0",
     "morgan": "^1.10.0",
     "stack54": "^0.14.0",
-    "svelte": "^4.2.8",
+    "svelte": "^5.51.5",
     "typed-htmx": "^0.3.1"
   },
   "devDependencies": {
diff --git a/templates/standalone/package.json b/templates/standalone/package.json
index 011df8a8..52f4167e 100644
--- a/templates/standalone/package.json
+++ b/templates/standalone/package.json
@@ -27,7 +27,7 @@
     "morgan": "^1.10.0",
     "postcss": "^8.5.6",
     "stack54": "^0.14.0",
-    "svelte": "^4.2.8",
+    "svelte": "^5.51.5",
     "tailwindcss": "^4.1.11"
   },
   "devDependencies": {
diff --git a/templates/tailwindcss/package.json b/templates/tailwindcss/package.json
index 2c27fc0f..de460b08 100644
--- a/templates/tailwindcss/package.json
+++ b/templates/tailwindcss/package.json
@@ -24,7 +24,7 @@
     "method-override": "^3.0.0",
     "morgan": "^1.10.0",
     "stack54": "^0.14.0",
-    "svelte": "^4.2.8"
+    "svelte": "^5.51.5"
   },
   "devDependencies": {
     "@playwright/test": "^1.46.1",