diff --git a/.eslintrc.json b/.eslintrc.json
new file mode 100644
index 0000000..338c655
--- /dev/null
+++ b/.eslintrc.json
@@ -0,0 +1,34 @@
+{
+  "env": {
+    "browser": true,
+    "es2021": true
+  },
+  "parser": "@typescript-eslint/parser",
+  "parserOptions": {
+    "ecmaFeatures": { "jsx": true },
+    "sourceType": "module"
+  },
+  "plugins": ["react", "react-hooks", "@typescript-eslint"],
+  "extends": [
+    "eslint:recommended",
+    "plugin:@typescript-eslint/recommended",
+    "plugin:react/recommended",
+    "plugin:react-hooks/recommended"
+  ],
+  "settings": {
+    "react": { "version": "detect" }
+  },
+  "rules": {
+    "react/react-in-jsx-scope": "off",
+    "@typescript-eslint/no-explicit-any": "error",
+    "@typescript-eslint/no-unused-vars": "warn"
+  },
+  "overrides": [
+    {
+      "files": ["**/*.test.ts", "**/*.test.tsx"],
+      "rules": {
+        "@typescript-eslint/no-require-imports": "off"
+      }
+    }
+  ]
+}
diff --git a/.github/workflows/ci.yaml b/.github/workflows/ci.yaml
index 9e57e30..ff4b233 100644
--- a/.github/workflows/ci.yaml
+++ b/.github/workflows/ci.yaml
@@ -34,6 +34,8 @@ jobs:
   test:
     runs-on: ubuntu-latest
     timeout-minutes: 10
+    permissions:
+      checks: write
     steps:
       - uses: actions/checkout@v4
       - uses: actions/setup-node@v4
diff --git a/src/components/OverviewPage.tsx b/src/components/OverviewPage.tsx
index 06ce770..f773e39 100644
--- a/src/components/OverviewPage.tsx
+++ b/src/components/OverviewPage.tsx
@@ -18,7 +18,7 @@ import React, { useCallback, useEffect, useState } from 'react';
 import { useTnsCsiContext } from '../api/TnsCsiDataContext';
 import { formatAge, formatProtocol, phaseToStatus } from '../api/k8s';
 import type { TnsCsiMetrics } from '../api/metrics';
-import { extractTnsCsiMetrics, fetchControllerMetrics, parsePrometheusText } from '../api/metrics';
+import { fetchControllerMetrics } from '../api/metrics';
 import DriverStatusCard from './DriverStatusCard';
 
 // ---------------------------------------------------------------------------
@@ -85,6 +85,24 @@ export default function OverviewPage() {
     void fetchMetrics();
   }, [fetchMetrics]);
 
+  const capacityByPool: Map<string, number> = React.useMemo(() => {
+    const map = new Map<string, number>();
+    if (!metrics) return map;
+    const handleToPool = new Map<string, string>();
+    for (const pv of persistentVolumes) {
+      const handle = pv.spec.csi?.volumeHandle;
+      const pool = pv.spec.csi?.volumeAttributes?.['pool'];
+      if (handle && pool) handleToPool.set(handle, pool);
+    }
+    for (const sample of metrics.volumeCapacityBytes) {
+      const volumeId = sample.labels['volume_id'];
+      if (!volumeId) continue;
+      const pool = handleToPool.get(volumeId) ?? 'unknown';
+      map.set(pool, (map.get(pool) ?? 0) + sample.value);
+    }
+    return map;
+  }, [metrics, persistentVolumes]);
+
   if (loading) {
     return <Loader title="Loading TNS-CSI data..." />;
   }
@@ -111,27 +129,6 @@ export default function OverviewPage() {
   const chartData = protocolChartData(storageClasses);
   const totalScs = storageClasses.length;
 
-  // Capacity by pool: join volumeCapacityBytes samples (volume_id, protocol)
-  // with PV volumeHandle → pool name from volumeAttributes.
-  const capacityByPool: Map<string, number> = React.useMemo(() => {
-    const map = new Map<string, number>();
-    if (!metrics) return map;
-    // Build lookup: volumeHandle → pool name
-    const handleToPool = new Map<string, string>();
-    for (const pv of persistentVolumes) {
-      const handle = pv.spec.csi?.volumeHandle;
-      const pool = pv.spec.csi?.volumeAttributes?.['pool'];
-      if (handle && pool) handleToPool.set(handle, pool);
-    }
-    for (const sample of metrics.volumeCapacityBytes) {
-      const volumeId = sample.labels['volume_id'];
-      if (!volumeId) continue;
-      const pool = handleToPool.get(volumeId) ?? 'unknown';
-      map.set(pool, (map.get(pool) ?? 0) + sample.value);
-    }
-    return map;
-  }, [metrics, persistentVolumes]);
-
   return (
     <>
       <div style={{ display: 'flex', justifyContent: 'space-between', alignItems: 'center', marginBottom: '20px' }}>