diff --git a/.jules/bolt.md b/.jules/bolt.md
index d54cf10f..c1abc36f 100644
--- a/.jules/bolt.md
+++ b/.jules/bolt.md
@@ -61,3 +61,4 @@
 ## 2026-07-13 - Array.from mapping optimization
 **Learning:** Using `Array.from({ length: N }).map(...)` creates an intermediate array of `undefined` values which requires memory allocation and garbage collection, adding O(N) unnecessary overhead in frequently re-rendered UI components.
 **Action:** Use `Array.from({ length: N }, (_, index) => ...)` to map elements directly during array creation, avoiding intermediate allocations.
+## 2026-11-23 - Avoid .every() for large array validation\n**Learning:** Using `Array.prototype.every()` for validating large byte arrays allocates an intermediate callback function repeatedly in a hot path, causing O(N) allocation overhead.\n**Action:** Use a standard `for` loop with an early `break` to keep memory usage at O(1) and improve execution speed.
diff --git a/apps/desktop/src/features/score/scoreStorage.test.ts b/apps/desktop/src/features/score/scoreStorage.test.ts
index 0feec199..235bf074 100644
--- a/apps/desktop/src/features/score/scoreStorage.test.ts
+++ b/apps/desktop/src/features/score/scoreStorage.test.ts
@@ -16,6 +16,15 @@ describe("scoreStorage bridge resolution", () => {
     delete tauriWindow.__TAURI_INVOKE__;
   });
 
+  it("fails closed when readScorePdf receives an invalid array (early exit for non-number)", async () => {
+    const tauriWindow = window as TauriWindow;
+    tauriWindow.__TAURI_INVOKE__ = vi.fn().mockResolvedValue([1, 2, "not-a-number", 4]);
+
+    await expect(readScorePdf("project-1", "score-1")).rejects.toThrow(
+      "Invalid score bridge response"
+    );
+  });
+
   it("fails closed on every command when there is no window (non-browser runtime)", async () => {
     // Simulate a runtime without a DOM window (e.g. SSR / bundler prerender):
     // getInvoke() must take the `typeof window === "undefined"` branch and
diff --git a/apps/desktop/src/features/score/scoreStorage.ts b/apps/desktop/src/features/score/scoreStorage.ts
index 492f1259..c011a207 100644
--- a/apps/desktop/src/features/score/scoreStorage.ts
+++ b/apps/desktop/src/features/score/scoreStorage.ts
@@ -91,8 +91,18 @@ export async function readScorePdf(projectId: string, scoreId: string): Promise<
   if (response instanceof ArrayBuffer) {
     return new Uint8Array(response);
   }
-  if (Array.isArray(response) && response.every((byte) => typeof byte === "number")) {
-    return Uint8Array.from(response as number[]);
+  if (Array.isArray(response)) {
+    // Performance: Avoid O(N) callback invocation overhead from .every()
+    let isDense = true;
+    for (let i = 0; i < response.length; i++) {
+      if (typeof response[i] !== "number") {
+        isDense = false;
+        break;
+      }
+    }
+    if (isDense) {
+      return Uint8Array.from(response as number[]);
+    }
   }
 
   throw new Error(INVALID_RESPONSE_MESSAGE);
diff --git a/package-lock.json b/package-lock.json
index cf1c991c..ff7604e4 100644
--- a/package-lock.json
+++ b/package-lock.json
@@ -955,7 +955,6 @@
       "os": [
         "aix"
       ],
-      "peer": true,
       "engines": {
         "node": ">=18"
       }
@@ -973,7 +972,6 @@
       "os": [
         "android"
       ],
-      "peer": true,
       "engines": {
         "node": ">=18"
       }
@@ -991,7 +989,6 @@
       "os": [
         "android"
       ],
-      "peer": true,
       "engines": {
         "node": ">=18"
       }
@@ -1009,7 +1006,6 @@
       "os": [
         "android"
       ],
-      "peer": true,
       "engines": {
         "node": ">=18"
       }
@@ -1027,7 +1023,6 @@
       "os": [
         "darwin"
       ],
-      "peer": true,
       "engines": {
         "node": ">=18"
       }
@@ -1045,7 +1040,6 @@
       "os": [
         "darwin"
       ],
-      "peer": true,
       "engines": {
         "node": ">=18"
       }
@@ -1063,7 +1057,6 @@
       "os": [
         "freebsd"
       ],
-      "peer": true,
       "engines": {
         "node": ">=18"
       }
@@ -1081,7 +1074,6 @@
       "os": [
         "freebsd"
       ],
-      "peer": true,
       "engines": {
         "node": ">=18"
       }
@@ -1099,7 +1091,6 @@
       "os": [
         "linux"
       ],
-      "peer": true,
       "engines": {
         "node": ">=18"
       }
@@ -1117,7 +1108,6 @@
       "os": [
         "linux"
       ],
-      "peer": true,
       "engines": {
         "node": ">=18"
       }
@@ -1135,7 +1125,6 @@
       "os": [
         "linux"
       ],
-      "peer": true,
       "engines": {
         "node": ">=18"
       }
@@ -1153,7 +1142,6 @@
       "os": [
         "linux"
       ],
-      "peer": true,
       "engines": {
         "node": ">=18"
       }
@@ -1171,7 +1159,6 @@
       "os": [
         "linux"
       ],
-      "peer": true,
       "engines": {
         "node": ">=18"
       }
@@ -1189,7 +1176,6 @@
       "os": [
         "linux"
       ],
-      "peer": true,
       "engines": {
         "node": ">=18"
       }
@@ -1207,7 +1193,6 @@
       "os": [
         "linux"
       ],
-      "peer": true,
       "engines": {
         "node": ">=18"
       }
@@ -1225,7 +1210,6 @@
       "os": [
         "linux"
       ],
-      "peer": true,
       "engines": {
         "node": ">=18"
       }
@@ -1243,7 +1227,6 @@
       "os": [
         "linux"
       ],
-      "peer": true,
       "engines": {
         "node": ">=18"
       }
@@ -1261,7 +1244,6 @@
       "os": [
         "netbsd"
       ],
-      "peer": true,
       "engines": {
         "node": ">=18"
       }
@@ -1279,7 +1261,6 @@
       "os": [
         "netbsd"
       ],
-      "peer": true,
       "engines": {
         "node": ">=18"
       }
@@ -1297,7 +1278,6 @@
       "os": [
         "openbsd"
       ],
-      "peer": true,
       "engines": {
         "node": ">=18"
       }
@@ -1315,7 +1295,6 @@
       "os": [
         "openbsd"
       ],
-      "peer": true,
       "engines": {
         "node": ">=18"
       }
@@ -1333,7 +1312,6 @@
       "os": [
         "openharmony"
       ],
-      "peer": true,
       "engines": {
         "node": ">=18"
       }
@@ -1351,7 +1329,6 @@
       "os": [
         "sunos"
       ],
-      "peer": true,
       "engines": {
         "node": ">=18"
       }
@@ -1369,7 +1346,6 @@
       "os": [
         "win32"
       ],
-      "peer": true,
       "engines": {
         "node": ">=18"
       }
@@ -1387,7 +1363,6 @@
       "os": [
         "win32"
       ],
-      "peer": true,
       "engines": {
         "node": ">=18"
       }
@@ -1405,7 +1380,6 @@
       "os": [
         "win32"
       ],
-      "peer": true,
       "engines": {
         "node": ">=18"
       }
@@ -7179,9 +7153,9 @@
       }
     },
     "node_modules/undici": {
-      "version": "7.28.0",
-      "resolved": "https://registry.npmjs.org/undici/-/undici-7.28.0.tgz",
-      "integrity": "sha512-cRZYrTDwWznlnRiPjggAGxZXanty6M8RV1ff8Wm4LWXBp7/IG8v5DnOm74DtUBp9OONpK75YlPnIjQqX0dBDtA==",
+      "version": "7.29.0",
+      "resolved": "https://registry.npmjs.org/undici/-/undici-7.29.0.tgz",
+      "integrity": "sha512-IDxfleLmmbSskfWSUATiN1nfn2rDuvnMOqb5CWR92iIfojA0Ud+ulOAAEQ57LPr9rWmsreUyf5lwyao+7GNNVw==",
       "dev": true,
       "license": "MIT",
       "engines": {