diff --git a/web/eslint.config.js b/web/eslint.config.js
index 3867729..8769989 100644
--- a/web/eslint.config.js
+++ b/web/eslint.config.js
@@ -23,10 +23,10 @@ export default defineConfig([
 
   js.configs.recommended,
   ...pluginVue.configs['flat/essential'],
-  
+
   {
     ...pluginVitest.configs.recommended,
-    files: ['src/**/__tests__/*'],
+    files: ['src/**/__tests__/*', 'src/test/**'],
   },
   skipFormatting,
 ])
diff --git a/web/src/stores/__tests__/butterfliu.spec.js b/web/src/stores/__tests__/butterfliu.spec.js
index bae1a90..476214e 100644
--- a/web/src/stores/__tests__/butterfliu.spec.js
+++ b/web/src/stores/__tests__/butterfliu.spec.js
@@ -1,4 +1,4 @@
-import { describe, it, expect, vi, beforeEach } from 'vitest'
+import { describe, it, expect, vi, beforeEach, afterEach } from 'vitest'
 import { useButterfliuStore } from '../butterfliu'
 
 describe('butterfliu store', () => {
@@ -6,13 +6,22 @@ describe('butterfliu store', () => {
     vi.restoreAllMocks()
   })
 
+  afterEach(() => {
+    vi.unstubAllGlobals()
+  })
+
+  function mockFetch(impl) {
+    vi.stubGlobal('fetch', vi.fn().mockImplementation(impl))
+    return fetch
+  }
+
   describe('fetchLibraries', () => {
     it('should fetch and set libraries on success', async () => {
       const mockLibs = [{ id: 1, name: 'Test Lib', path: '/music' }]
-      global.fetch = vi.fn().mockResolvedValue({
+      mockFetch(() => Promise.resolve({
         ok: true,
         json: () => Promise.resolve(mockLibs),
-      })
+      }))
 
       const store = useButterfliuStore()
       await store.fetchLibraries()
@@ -22,10 +31,10 @@ describe('butterfliu store', () => {
     })
 
     it('should set error on failure', async () => {
-      global.fetch = vi.fn().mockResolvedValue({
+      mockFetch(() => Promise.resolve({
         ok: false,
         status: 500,
-      })
+      }))
 
       const store = useButterfliuStore()
       await store.fetchLibraries()
@@ -34,7 +43,7 @@ describe('butterfliu store', () => {
     })
 
     it('should set error on network failure', async () => {
-      global.fetch = vi.fn().mockRejectedValue(new Error('Network error'))
+      mockFetch(() => Promise.reject(new Error('Network error')))
 
       const store = useButterfliuStore()
       await store.fetchLibraries()
@@ -46,25 +55,25 @@ describe('butterfliu store', () => {
   describe('scanLibrary', () => {
     it('should POST to scan endpoint and return result', async () => {
       const mockResult = { added: 5, updated: 2 }
-      global.fetch = vi.fn().mockResolvedValue({
+      const fetchMock = mockFetch(() => Promise.resolve({
         ok: true,
         json: () => Promise.resolve(mockResult),
-      })
+      }))
 
       const store = useButterfliuStore()
       const result = await store.scanLibrary(1)
 
       expect(result).toEqual(mockResult)
-      expect(global.fetch).toHaveBeenCalledWith('/api/libraries/1/scan', {
+      expect(fetchMock).toHaveBeenCalledWith('/api/libraries/1/scan', {
         method: 'POST',
       })
     })
 
     it('should set error on failure', async () => {
-      global.fetch = vi.fn().mockResolvedValue({
+      mockFetch(() => Promise.resolve({
         ok: false,
         status: 404,
-      })
+      }))
 
       const store = useButterfliuStore()
       const result = await store.scanLibrary(99)
@@ -77,16 +86,16 @@ describe('butterfliu store', () => {
   describe('addLibrary', () => {
     it('should POST to libraries endpoint with name and path', async () => {
       const mockLib = { id: 1, name: 'New Lib', path: '/new' }
-      global.fetch = vi.fn().mockResolvedValue({
+      const fetchMock = mockFetch(() => Promise.resolve({
         ok: true,
         json: () => Promise.resolve(mockLib),
-      })
+      }))
 
       const store = useButterfliuStore()
       const result = await store.addLibrary('New Lib', '/new')
 
       expect(result).toEqual(mockLib)
-      expect(global.fetch).toHaveBeenCalledWith('/api/libraries', {
+      expect(fetchMock).toHaveBeenCalledWith('/api/libraries', {
         method: 'POST',
         headers: { 'Content-Type': 'application/json' },
         body: JSON.stringify({ name: 'New Lib', path: '/new' }),
@@ -94,10 +103,10 @@ describe('butterfliu store', () => {
     })
 
     it('should set error on failure', async () => {
-      global.fetch = vi.fn().mockResolvedValue({
+      mockFetch(() => Promise.resolve({
         ok: false,
         status: 400,
-      })
+      }))
 
       const store = useButterfliuStore()
       const result = await store.addLibrary('Bad', '/path')
@@ -110,25 +119,25 @@ describe('butterfliu store', () => {
   describe('deleteLibrary', () => {
     it('should DELETE the library', async () => {
       const mockResult = { success: true }
-      global.fetch = vi.fn().mockResolvedValue({
+      const fetchMock = mockFetch(() => Promise.resolve({
         ok: true,
         json: () => Promise.resolve(mockResult),
-      })
+      }))
 
       const store = useButterfliuStore()
       const result = await store.deleteLibrary(1)
 
       expect(result).toEqual(mockResult)
-      expect(global.fetch).toHaveBeenCalledWith('/api/libraries/1', {
+      expect(fetchMock).toHaveBeenCalledWith('/api/libraries/1', {
         method: 'DELETE',
       })
     })
 
     it('should set error on failure', async () => {
-      global.fetch = vi.fn().mockResolvedValue({
+      mockFetch(() => Promise.resolve({
         ok: false,
         status: 500,
-      })
+      }))
 
       const store = useButterfliuStore()
       const result = await store.deleteLibrary(1)
@@ -141,10 +150,10 @@ describe('butterfliu store', () => {
   describe('fetchLibrarySongs', () => {
     it('should fetch songs for a library', async () => {
       const mockSongs = [{ id: 1, title: 'Song 1' }]
-      global.fetch = vi.fn().mockResolvedValue({
+      mockFetch(() => Promise.resolve({
         ok: true,
         json: () => Promise.resolve(mockSongs),
-      })
+      }))
 
       const store = useButterfliuStore()
       const songs = await store.fetchLibrarySongs(1)
@@ -153,10 +162,10 @@ describe('butterfliu store', () => {
     })
 
     it('should throw on failure', async () => {
-      global.fetch = vi.fn().mockResolvedValue({
+      mockFetch(() => Promise.resolve({
         ok: false,
         status: 500,
-      })
+      }))
 
       const store = useButterfliuStore()
       await expect(store.fetchLibrarySongs(1)).rejects.toThrow('HTTP 500')
@@ -169,23 +178,23 @@ describe('butterfliu store', () => {
         { id: 1, title: 'Song 1' },
         { id: 2, title: 'Song 2' },
       ]
-      global.fetch = vi.fn().mockResolvedValue({
+      const fetchMock = mockFetch(() => Promise.resolve({
         ok: true,
         json: () => Promise.resolve(mockSongs),
-      })
+      }))
 
       const store = useButterfliuStore()
       const songs = await store.fetchAllSongs()
 
       expect(songs).toEqual(mockSongs)
-      expect(global.fetch).toHaveBeenCalledWith('/api/songs')
+      expect(fetchMock).toHaveBeenCalledWith('/api/songs')
     })
 
     it('should throw on failure', async () => {
-      global.fetch = vi.fn().mockResolvedValue({
+      mockFetch(() => Promise.resolve({
         ok: false,
         status: 503,
-      })
+      }))
 
       const store = useButterfliuStore()
       await expect(store.fetchAllSongs()).rejects.toThrow('HTTP 503')
@@ -195,10 +204,10 @@ describe('butterfliu store', () => {
   describe('fetchArtists', () => {
     it('should fetch artists', async () => {
       const mockArtists = ['Artist 1', 'Artist 2']
-      global.fetch = vi.fn().mockResolvedValue({
+      mockFetch(() => Promise.resolve({
         ok: true,
         json: () => Promise.resolve(mockArtists),
-      })
+      }))
 
       const store = useButterfliuStore()
       const artists = await store.fetchArtists()
@@ -210,10 +219,10 @@ describe('butterfliu store', () => {
   describe('fetchAlbums', () => {
     it('should fetch albums', async () => {
       const mockAlbums = ['Album 1', 'Album 2']
-      global.fetch = vi.fn().mockResolvedValue({
+      mockFetch(() => Promise.resolve({
         ok: true,
         json: () => Promise.resolve(mockAlbums),
-      })
+      }))
 
       const store = useButterfliuStore()
       const albums = await store.fetchAlbums()
diff --git a/web/src/test/setup.js b/web/src/test/setup.js
index 4c0a10c..7bb27cf 100644
--- a/web/src/test/setup.js
+++ b/web/src/test/setup.js
@@ -52,7 +52,7 @@ class MockAudio {
   }
 }
 
-global.Audio = MockAudio
+globalThis.Audio = MockAudio
 
 beforeEach(() => {
   setActivePinia(createPinia())