diff --git a/package.json b/package.json
index cc31166e..48c9f541 100644
--- a/package.json
+++ b/package.json
@@ -18,11 +18,11 @@
     "build:desktop-only": "pnpm -F @prompt-optimizer/desktop build",
     "build:desktop": "npm-run-all build:core build:ui build:web build:desktop-only",
     "dev": "npm-run-all clean:dist build:core build:ui dev:parallel",
-    "dev:fresh": "npm-run-all clean pnpm-install dev",
+    "dev:fresh": "npm-run-all kill:dev clean pnpm-install dev",
     "dev:parallel": "concurrently -k -p \"[{name}]\" -n \"UI,WEB\" \"pnpm -F @prompt-optimizer/ui build --watch\" \"pnpm -F @prompt-optimizer/web dev\"",
     "dev:ext": "pnpm -F @prompt-optimizer/extension dev",
     "dev:desktop": "npm-run-all clean:dist build:core build:ui dev:desktop:parallel",
-    "dev:desktop:fresh": "npm-run-all clean pnpm-install dev:desktop",
+    "dev:desktop:fresh": "npm-run-all kill:dev clean pnpm-install dev:desktop",
     "dev:desktop:parallel": "concurrently -k -p \"[{name}]\" -n \"WEB,DESKTOP\" \"pnpm -F @prompt-optimizer/web dev\" \"pnpm -F @prompt-optimizer/desktop dev\"",
     "test": "pnpm -r test --run --passWithNoTests",
     "test:e2e": "playwright test",
@@ -45,7 +45,8 @@
     "lint:fix": "pnpm -F @prompt-optimizer/ui lint:fix",
     "bmad:refresh": "bmad-method install -f -i codex",
     "bmad:list": "bmad-method list:agents",
-    "bmad:validate": "bmad-method validate"
+    "bmad:validate": "bmad-method validate",
+    "kill:dev": "node scripts/kill-dev.js"
   },
   "devDependencies": {
     "@intlify/unplugin-vue-i18n": "^6.0.3",
diff --git a/scripts/kill-dev.js b/scripts/kill-dev.js
new file mode 100644
index 00000000..a23cc123
--- /dev/null
+++ b/scripts/kill-dev.js
@@ -0,0 +1,138 @@
+/**
+ * kill-dev v2 - Ultimate Safe Process Cleanup Script
+ *
+ * Strategy:
+ * 1. Clean up processes occupying ports (most critical)
+ * 2. Wait 2 seconds for parent processes to exit naturally
+ * 3. Check ports again to ensure complete cleanup
+ *
+ * About "missed processes":
+ * - Parent processes (pnpm) usually exit automatically after child processes terminate
+ * - vite build --watch doesn't occupy ports, exits with parent process
+ * - Even if missed, they don't occupy ports and won't block new starts
+ */
+
+const { execSync } = require('child_process');
+const os = require('os');
+
+console.log('🧹 Safely cleaning up project development processes...\n');
+
+// Limit to project-specific ports so we do not kill other apps using defaults like 5173
+const PORTS = [18181];
+
+/**
+ * Cross-platform non-blocking sleep
+ */
+function wait(ms) {
+  return new Promise((resolve) => setTimeout(resolve, ms));
+}
+
+function killByPorts(round = 1) {
+  const platform = os.platform();
+  let killedCount = 0;
+  const killedPids = new Set();
+
+  console.log(`🔍 Round ${round}: Checking port occupation...`);
+
+  if (platform === 'win32') {
+    for (const port of PORTS) {
+      try {
+        const output = execSync(`netstat -ano | findstr ":${port}"`, {
+          encoding: 'utf-8',
+          stdio: 'pipe'
+        });
+
+        // Windows uses \r\n, so split by \n and trim each line
+        const lines = output.split('\n').map(line => line.trim()).filter(Boolean);
+        lines.forEach(line => {
+          const match = line.match(/LISTENING\s+(\d+)/);
+          if (match && !killedPids.has(match[1])) {
+            const pid = match[1];
+            try {
+              execSync(`taskkill /F /PID ${pid}`, { stdio: 'pipe' });
+              console.log(`  ✓ Killed process on port ${port} (PID: ${pid})`);
+              killedPids.add(pid);
+              killedCount++;
+            } catch (e) {
+              // Process may have already exited
+            }
+          }
+        });
+      } catch (error) {
+        // Port not occupied or command failed
+      }
+    }
+  } else {
+    for (const port of PORTS) {
+      try {
+        const output = execSync(`lsof -ti :${port}`, {
+          encoding: 'utf-8',
+          stdio: 'pipe'
+        });
+
+        const pids = output.split('\n').map(pid => pid.trim()).filter(Boolean);
+        pids.forEach(pid => {
+          if (!killedPids.has(pid)) {
+            try {
+              execSync(`kill -9 ${pid}`, { stdio: 'pipe' });
+              console.log(`  ✓ Killed process on port ${port} (PID: ${pid})`);
+              killedPids.add(pid);
+              killedCount++;
+            } catch (e) {
+              // Process may have already exited
+            }
+          }
+        });
+      } catch (error) {
+        // Port not occupied or command failed
+      }
+    }
+  }
+
+  if (killedCount === 0) {
+    console.log('  ℹ️  No processes found occupying ports');
+  }
+
+  return killedCount;
+}
+
+async function main() {
+  try {
+    // First round cleanup
+    let totalKilled = killByPorts(1);
+
+    if (totalKilled > 0) {
+      // Wait for parent processes to exit naturally (cross-platform)
+      console.log('\n⏳ Waiting 2 seconds for parent processes to exit naturally...\n');
+      await wait(2000);
+
+      // Second round cleanup (ensure no missed processes)
+      const round2Killed = killByPorts(2);
+      totalKilled += round2Killed;
+
+      if (round2Killed > 0) {
+        console.log('\n💡 Found and cleaned up missed processes');
+      } else {
+        console.log('\n✅ Confirmed: All processes completely cleaned up');
+      }
+    }
+
+    console.log(`\n📊 Total cleaned: ${totalKilled} process(es)`);
+
+    if (totalKilled > 0) {
+      console.log('✅ Cleanup complete! You can now run pnpm dev:fresh');
+    } else {
+      console.log('ℹ️  No processes found that need cleanup');
+    }
+
+    process.exit(0);
+  } catch (error) {
+    console.error('\n❌ Cleanup failed:', error.message);
+    console.error('\n💡 Please try:');
+    console.error('   1. Run this script again');
+    console.error('   2. Or manually terminate related processes in Task Manager');
+    process.exit(1);
+  }
+}
+
+main();