diff --git a/webui/src/components/__tests__/InstanceList.test.tsx b/webui/src/components/__tests__/InstanceList.test.tsx
index 01d8c25..a6924b7 100644
--- a/webui/src/components/__tests__/InstanceList.test.tsx
+++ b/webui/src/components/__tests__/InstanceList.test.tsx
@@ -4,8 +4,7 @@ import userEvent from '@testing-library/user-event'
 import InstanceList from '@/components/InstanceList'
 import { InstancesProvider } from '@/contexts/InstancesContext'
 import { instancesApi } from '@/lib/api'
-import type { Instance } from '@/types/instance'
-import { BackendType } from '@/types/instance'
+import { BackendType, type Instance } from '@/types/instance'
 import { AuthProvider } from '@/contexts/AuthContext'
 
 // Mock the API
diff --git a/webui/src/components/form/KeyValueInput.tsx b/webui/src/components/form/KeyValueInput.tsx
index 62585c4..f136ecd 100644
--- a/webui/src/components/form/KeyValueInput.tsx
+++ b/webui/src/components/form/KeyValueInput.tsx
@@ -59,7 +59,7 @@ const KeyValueInput: React.FC<KeyValueInputProps> = ({
       // Reset to single empty row if value is explicitly undefined/null
       setPairs([{ key: '', value: '' }])
     }
-    // eslint-disable-next-line react-hooks/exhaustive-deps
+     
   }, [value])
 
   // Update parent component when pairs change
diff --git a/webui/src/contexts/__tests__/InstancesContext.test.tsx b/webui/src/contexts/__tests__/InstancesContext.test.tsx
index cad603d..1f99055 100644
--- a/webui/src/contexts/__tests__/InstancesContext.test.tsx
+++ b/webui/src/contexts/__tests__/InstancesContext.test.tsx
@@ -3,8 +3,7 @@ import { render, screen, waitFor } from "@testing-library/react";
 import type { ReactNode } from "react";
 import { InstancesProvider, useInstances } from "@/contexts/InstancesContext";
 import { instancesApi } from "@/lib/api";
-import type { Instance } from "@/types/instance";
-import { BackendType } from "@/types/instance";
+import { BackendType, type Instance } from "@/types/instance";
 import { AuthProvider } from "../AuthContext";
 
 // Mock the API module
diff --git a/webui/src/lib/healthService.ts b/webui/src/lib/healthService.ts
index 7d47486..46cfcdf 100644
--- a/webui/src/lib/healthService.ts
+++ b/webui/src/lib/healthService.ts
@@ -156,11 +156,14 @@ class HealthService {
       this.callbacks.set(instanceName, new Set())
     }
 
-    this.callbacks.get(instanceName)!.add(callback)
+    const callbacks = this.callbacks.get(instanceName)
+    if (callbacks) {
+      callbacks.add(callback)
 
-    // Start health checking if this is the first subscriber
-    if (this.callbacks.get(instanceName)!.size === 1) {
-      this.startHealthCheck(instanceName)
+      // Start health checking if this is the first subscriber
+      if (callbacks.size === 1) {
+        this.startHealthCheck(instanceName)
+      }
     }
 
     // Return unsubscribe function
@@ -214,22 +217,24 @@ class HealthService {
     }
 
     // Start new interval with appropriate timing
-    const interval = setInterval(async () => {
-      try {
-        const health = await this.performHealthCheck(instanceName)
-        this.notifyCallbacks(instanceName, health)
+    const interval = setInterval(() => {
+      void (async () => {
+        try {
+          const health = await this.performHealthCheck(instanceName)
+          this.notifyCallbacks(instanceName, health)
 
-        // Check if state changed and adjust interval
-        const previousState = this.lastHealthState.get(instanceName)
-        this.lastHealthState.set(instanceName, health.state)
+          // Check if state changed and adjust interval
+          const previousState = this.lastHealthState.get(instanceName)
+          this.lastHealthState.set(instanceName, health.state)
 
-        if (previousState !== health.state) {
-          this.adjustPollingInterval(instanceName, health.state)
+          if (previousState !== health.state) {
+            this.adjustPollingInterval(instanceName, health.state)
+          }
+        } catch (error) {
+          console.error(`Health check failed for ${instanceName}:`, error)
+          // Continue polling even on error
         }
-      } catch (error) {
-        console.error(`Health check failed for ${instanceName}:`, error)
-        // Continue polling even on error
-      }
+      })()
     }, pollInterval)
 
     this.intervals.set(instanceName, interval)
diff --git a/webui/src/main.tsx b/webui/src/main.tsx
index 6418a1e..085ab4f 100644
--- a/webui/src/main.tsx
+++ b/webui/src/main.tsx
@@ -6,7 +6,10 @@ import './index.css'
 import { AuthProvider } from './contexts/AuthContext'
 import { ConfigProvider } from './contexts/ConfigContext'
 
-ReactDOM.createRoot(document.getElementById('root')!).render(
+const rootElement = document.getElementById('root')
+if (!rootElement) throw new Error('Failed to find the root element')
+
+ReactDOM.createRoot(rootElement).render(
   <React.StrictMode>
     <AuthProvider>
       <ConfigProvider>