diff --git a/.jules/sentinel.md b/.jules/sentinel.md
new file mode 100644
index 0000000..85cdc4c
--- /dev/null
+++ b/.jules/sentinel.md
@@ -0,0 +1,4 @@
+## 2023-10-25 - [Command Injection Risk]
+**Vulnerability:** Use of `execSync` with a string interpolated path in `reconcile.ts` (`execSync(\`node --check "\${tempFile}"\`)`) opened up a command injection risk if the file path was ever attacker-controlled or contained quotes/shell metacharacters.
+**Learning:** Even internal file paths (`path.join` with `options.workspace`) shouldn't be blindly trusted to shell execution (`execSync` or `spawn` with `shell: true`), as quotes or shell metacharacters could still technically cause escaping depending on OS path characteristics or upstream workspace configuration.
+**Prevention:** Use `spawnSync` (or `spawn`) with an explicit argument array (`["--check", tempFile]`) and avoid shell execution. For Node scripts, invoke `process.execPath` explicitly instead of depending on `node` in the PATH string.
diff --git a/packages/core/src/reconcile.ts b/packages/core/src/reconcile.ts
index b0285bc..8ba29d2 100644
--- a/packages/core/src/reconcile.ts
+++ b/packages/core/src/reconcile.ts
@@ -1,4 +1,4 @@
-import { execSync } from "node:child_process";
+import { spawnSync } from "node:child_process";
 import crypto from "node:crypto";
 import fs from "node:fs";
 import path from "node:path";
@@ -139,7 +139,10 @@ export function reconcile(options: ReconcileOptions): ReconcileResult {
   fs.writeFileSync(tempFile, extractedCode, "utf8");
 
   try {
-    execSync(`node --check "${tempFile}"`, { stdio: "pipe" });
+    const checkResult = spawnSync(process.execPath, ["--check", tempFile], { stdio: "pipe", encoding: "utf8" });
+    if (checkResult.status !== 0) {
+      throw new Error(checkResult.stderr || checkResult.stdout || "Syntax check failed");
+    }
     log.audit("Syntax check passed");
   } catch (err) {
     const stderr =