diff --git a/.changeset/solid-js-peer.md b/.changeset/solid-js-peer.md
new file mode 100644
index 000000000..e73a2b59e
--- /dev/null
+++ b/.changeset/solid-js-peer.md
@@ -0,0 +1,5 @@
+---
+"@solidjs/start": patch
+---
+
+Make `solid-js` a peer dependency instead of a regular one. When an app's `solid-js` version was outside the range SolidStart asked for, package managers installed a second copy just for SolidStart. The two copies did not share reactive context, so client-side navigation broke with `TypeError: Cannot read properties of null (reading 'push')`. SolidStart now uses the app's `solid-js`, and a version outside the supported range shows up as a peer dependency warning at install time.
diff --git a/packages/start/package.json b/packages/start/package.json
index a6137a0d4..106d79b19 100644
--- a/packages/start/package.json
+++ b/packages/start/package.json
@@ -79,7 +79,6 @@
     "seroval": "^1.6.8",
     "seroval-plugins": "^1.6.8",
     "shiki": "^4.3.1",
-    "solid-js": "^1.9.15",
     "srvx": "^0.12.4",
     "terracotta": "^1.2.4",
     "vite-plugin-solid": "^2.11.13"
@@ -87,11 +86,13 @@
   "devDependencies": {
     "@types/babel__core": "^7.20.5",
     "@types/node": "^26.1.1",
+    "solid-js": "^1.9.15",
     "vite": "^8.1.5",
     "vitest": "^4.1.10"
   },
   "peerDependencies": {
     "@solidjs/router": ">=0.16.0 <2.0.0-0",
+    "solid-js": "^1.9.15",
     "vite": "^8 || ^9"
   },
   "peerDependenciesMeta": {
diff --git a/pnpm-lock.yaml b/pnpm-lock.yaml
index 65b914178..6b1868754 100644
--- a/pnpm-lock.yaml
+++ b/pnpm-lock.yaml
@@ -377,9 +377,6 @@ importers:
       shiki:
         specifier: ^4.3.1
         version: 4.3.1
-      solid-js:
-        specifier: ^1.9.15
-        version: 1.9.15
       srvx:
         specifier: ^0.12.4
         version: 0.12.4
@@ -396,6 +393,9 @@ importers:
       '@types/node':
         specifier: ^26.1.1
         version: 26.1.1
+      solid-js:
+        specifier: ^1.9.15
+        version: 1.9.15
       vite:
         specifier: ^8.1.5
         version: 8.1.5(@types/node@26.1.1)(esbuild@0.27.4)(jiti@2.7.0)(terser@5.46.0)