From 3d422a5e6e1c8b0c4c061f66c4ad21550de2888d Mon Sep 17 00:00:00 2001
From: Claude <noreply@anthropic.com>
Date: Mon, 10 Aug 2026 23:25:24 +0000
Subject: [PATCH 1/2] feat: fail clearly on unsupported 32-bit build machines

---
 README.md                          | 10 ++++++++++
 package.json                       |  4 ++++
 script/select-7z-arch.js           |  7 ++++++-
 spec/assert-supported-arch-spec.ts | 12 ++++++++++++
 src/index.ts                       | 15 +++++++++++++++
 5 files changed, 47 insertions(+), 1 deletion(-)
 create mode 100644 spec/assert-supported-arch-spec.ts

diff --git a/README.md b/README.md
index a0d9c13e..7fd7cce1 100644
--- a/README.md
+++ b/README.md
@@ -13,6 +13,16 @@ NPM module that builds Windows installers for
 npm install --save-dev electron-winstaller
 ```
 
+## Supported platforms
+
+Installers can be created on x64 and arm64 build machines (Windows, or
+macOS/Linux with Wine and Mono). 32-bit build machines are not supported —
+if you are on 64-bit Windows, make sure you are running 64-bit Node.js.
+
+Apps targeting 32-bit Windows (Electron <= 43) can still be packaged from
+a 64-bit machine; the generated installer runs on 32-bit Windows. Electron
+44 and later do not ship 32-bit Windows builds.
+
 ## Usage
 
 Require the package:
diff --git a/package.json b/package.json
index 887508af..b81c28d7 100644
--- a/package.json
+++ b/package.json
@@ -54,6 +54,10 @@
   "engines": {
     "node": ">=8.0.0"
   },
+  "cpu": [
+    "x64",
+    "arm64"
+  ],
   "publishConfig": {
     "provenance": true
   },
diff --git a/script/select-7z-arch.js b/script/select-7z-arch.js
index 7be25c8c..4d68ada1 100644
--- a/script/select-7z-arch.js
+++ b/script/select-7z-arch.js
@@ -5,7 +5,12 @@ const os = require('os');
  * Even if we're cross-compiling for a different arch like arm64,
  * we still need to use the 7-Zip executable for the host arch
  */
-const arch = os.arch;
+const arch = os.arch();
+
+if (arch !== 'x64' && arch !== 'arm64') {
+    console.warn('electron-winstaller: 32-bit build machines are not supported; installer creation will fail on this machine.');
+    process.exit(0);
+}
 
 console.log('Selecting 7-Zip for arch ' + arch);
 
diff --git a/spec/assert-supported-arch-spec.ts b/spec/assert-supported-arch-spec.ts
new file mode 100644
index 00000000..04e4a5fa
--- /dev/null
+++ b/spec/assert-supported-arch-spec.ts
@@ -0,0 +1,12 @@
+import test from 'ava';
+import { assertSupportedArch } from '../src/index';
+
+test('throws for 32-bit architectures', (t): void => {
+  t.throws(() => assertSupportedArch('ia32'), { message: '32-bit build machines are not supported' });
+  t.throws(() => assertSupportedArch('arm'), { message: '32-bit build machines are not supported' });
+});
+
+test('does not throw for 64-bit architectures', (t): void => {
+  t.notThrows(() => assertSupportedArch('x64'));
+  t.notThrows(() => assertSupportedArch('arm64'));
+});
diff --git a/src/index.ts b/src/index.ts
index c3148696..30c1d99e 100644
--- a/src/index.ts
+++ b/src/index.ts
@@ -47,6 +47,19 @@ export function sanitizeAuthors(authors: string): string {
   return authors.replace(/@/g, '');
 }
 
+/**
+ * Asserts that the host architecture is supported. Installer creation
+ * requires an x64 or arm64 build machine; the bundled 7-Zip, NuGet, and
+ * Squirrel tooling cannot run on 32-bit hosts.
+ *
+ * @param arch The host architecture, as reported by `process.arch`
+ */
+export function assertSupportedArch(arch: string = process.arch): void {
+  if (arch !== 'x64' && arch !== 'arm64') {
+    throw new Error('32-bit build machines are not supported');
+  }
+}
+
 function checkIfCommandExists(command: string): Promise<boolean> {
   const checkCommand = os.platform() === 'win32' ? 'where' : 'which';
   return new Promise((resolve) => {
@@ -64,6 +77,8 @@ function checkIfCommandExists(command: string): Promise<boolean> {
  * @see {@link https://github.com/Squirrel/Squirrel.Windows | Squirrel.Windows}
  */
 export async function createWindowsInstaller(options: SquirrelWindowsOptions): Promise<void> {
+  assertSupportedArch();
+
   let useMono = false;
 
   const monoExe = 'mono';

From b6d4879b53e8ab931976185cd6f11ad3f52499cb Mon Sep 17 00:00:00 2001
From: Claude <noreply@anthropic.com>
Date: Tue, 11 Aug 2026 00:47:12 +0000
Subject: [PATCH 2/2] fix: drop cpu field from package.json

Co-Authored-By: Claude Fable 5 <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_01SeZVGwhnCwgbxNcio8oiFo
---
 package.json | 4 ----
 1 file changed, 4 deletions(-)

diff --git a/package.json b/package.json
index b81c28d7..887508af 100644
--- a/package.json
+++ b/package.json
@@ -54,10 +54,6 @@
   "engines": {
     "node": ">=8.0.0"
   },
-  "cpu": [
-    "x64",
-    "arm64"
-  ],
   "publishConfig": {
     "provenance": true
   },