Replace regedit with handrolled utility

package.json

@@ -56,6 +56,7 @@
     "@types/jest": "^29.2.4",
     "@types/node": "^25.6.2",
     "eslint": "^10.3.0",
+    "eslint-config-prettier": "^10.1.8",
     "eslint-plugin-prettier": "^5.5.5",
     "jiti": "latest",
     "globals": "^17.6.0",
@@ -71,8 +72,7 @@
   },
   "dependencies": {
     "debug": "^4.3.4",
-    "ini": "^2.0.0",
-    "regedit": "^5.1.1"
+    "ini": "^2.0.0"
   },
   "engines": {
     "node": ">=20.17.0",

src/utils/registry.ts

@@ -1,21 +1,54 @@
-import regedit from 'regedit';
+import { execFile } from 'child_process';
+import * as Path from 'path';
+
+// Matches a value line from `reg query`, e.g. "    Name    REG_SZ    data".
+const VALUE_LINE = /^ {4}(.*?) {4}(REG_[A-Z_]+)(?: {4}(.*))?$/;
 
 /**
  * Returns `undefined` if the key does not exist.
  */
 export function readRegistryValue(key: string, subKey: string): Promise<string | undefined> {
+    if (process.platform !== 'win32') return Promise.resolve(undefined);
+
+    const regExe = Path.join(process.env.SystemRoot ?? 'C:\\Windows', 'System32', 'reg.exe');
+
     return new Promise<string | undefined>((resolve, reject) => {
-        regedit.list([key], (err, result) => {
-            if (err) {
-                reject(new Error(`Failed to read registry value ${key} (${err})`));
-            } else {
-                const values = result[key]?.values ?? {};
-                if (subKey in values) {
-                    resolve(values[subKey]!.value as string);
+        execFile(
+            regExe,
+            ['query', key, '/v', subKey],
+            { windowsHide: true },
+            (err, stdout, stderr) => {
+                if (err) {
+                    // reg exits with 1 when the key or value is missing
+                    if (err.code === 1) {
+                        resolve(undefined);
+                    } else {
+                        reject(
+                            new Error(
+                                `Failed to read registry value ${key} (${stderr.trim() || err.message})`
+                            )
+                        );
+                    }
                 } else {
-                    resolve(undefined);
+                    resolve(parseRegQueryOutput(stdout, subKey));
                 }
             }
-        });
+        );
     });
 }
+
+export function parseRegQueryOutput(stdout: string, valueName: string): string | undefined {
+    for (const line of stdout.split(/\r?\n/)) {
+        const match = VALUE_LINE.exec(line);
+        if (match && match[1]!.toLowerCase() === valueName.toLowerCase()) {
+            const type = match[2]!;
+            const data = match[3] ?? '';
+            // reg prints DWORD/QWORD as hex, callers expect decimal
+            if (type === 'REG_DWORD' || type === 'REG_QWORD') {
+                return BigInt(data).toString();
+            }
+            return data;
+        }
+    }
+    return undefined;
+}