diff --git a/packages/react-query/src/bin/postinstall.spec.ts b/packages/react-query/src/bin/postinstall.spec.ts
new file mode 100644
index 000000000..2428a487b
--- /dev/null
+++ b/packages/react-query/src/bin/postinstall.spec.ts
@@ -0,0 +1,53 @@
+import { beforeEach, describe, expect, it, vi } from 'vitest'
+import { getTanStackReactQueryPackageJson } from './utils/package'
+import { switchVersion } from './utils/switchVersion'
+
+vi.mock('./utils/package')
+vi.mock('./utils/switchVersion')
+
+describe('postinstall', () => {
+  const mockConsoleWarn = vi.spyOn(console, 'warn')
+  const mockGetTanStackReactQueryPackageJson = vi.mocked(getTanStackReactQueryPackageJson)
+  const mockSwitchVersion = vi.mocked(switchVersion)
+
+  const runPostInstall = async (version: string) => {
+    mockGetTanStackReactQueryPackageJson.mockReturnValue({
+      name: 'tanstack-query',
+      version,
+      description: `TanStack Query v${version.split('.')[0]}`,
+    })
+
+    await import('./postinstall')
+  }
+
+  beforeEach(() => {
+    vi.resetModules()
+    vi.clearAllMocks()
+  })
+
+  it('should switch to @suspensive/react-query-4 when @tanstack/react-query@^4 is installed', async () => {
+    await runPostInstall('4.2.3')
+
+    expect(mockGetTanStackReactQueryPackageJson).toHaveBeenCalledTimes(1)
+    expect(mockSwitchVersion).toHaveBeenCalledWith(4)
+    expect(mockSwitchVersion).toHaveBeenCalledTimes(1)
+    expect(mockConsoleWarn).not.toHaveBeenCalled()
+  })
+
+  it('should switch to @suspensive/react-query-5 when @tanstack/react-query@^5 is installed', async () => {
+    await runPostInstall('5.2.3')
+
+    expect(mockGetTanStackReactQueryPackageJson).toHaveBeenCalledTimes(1)
+    expect(mockSwitchVersion).toHaveBeenCalledWith(5)
+    expect(mockSwitchVersion).toHaveBeenCalledTimes(1)
+    expect(mockConsoleWarn).not.toHaveBeenCalled()
+  })
+
+  it('should show warning when unsupported version is installed', async () => {
+    await runPostInstall('3.3.4')
+
+    expect(mockGetTanStackReactQueryPackageJson).toHaveBeenCalledTimes(1)
+    expect(mockSwitchVersion).not.toHaveBeenCalled()
+    expect(mockConsoleWarn).toHaveBeenCalledWith('[@suspensive/react-query]', 'version v3.3.4 is not supported.')
+  })
+})
diff --git a/packages/react-query/src/bin/utils/package.spec.ts b/packages/react-query/src/bin/utils/package.spec.ts
index 0c04f64e5..3d68eae1d 100644
--- a/packages/react-query/src/bin/utils/package.spec.ts
+++ b/packages/react-query/src/bin/utils/package.spec.ts
@@ -3,6 +3,7 @@ import packageJson from '../../../package.json'
 import {
   getPackageJson,
   getSuspensiveReactQueryPackageJson,
+  getTanStackReactQueryAPIs,
   getTanStackReactQueryPackageJson,
   getTargetSuspensiveReactQueryAPIs,
   getTargetSuspensiveReactQueryVersion,
@@ -64,6 +65,30 @@ describe('package', () => {
     expect(result).toBeDefined()
     expect(result.name).toBe('@suspensive/react-query-4')
   })
+
+  it('should return correct APIs for version 5', () => {
+    const apis = getTanStackReactQueryAPIs('5')
+
+    expect(apis).toEqual([
+      'useSuspenseQuery',
+      'useSuspenseQueries',
+      'useSuspenseInfiniteQuery',
+      'usePrefetchQuery',
+      'usePrefetchInfiniteQuery',
+      'queryOptions',
+      'infiniteQueryOptions',
+    ])
+  })
+
+  it('should return placeholder for version 4', () => {
+    const apis = getTanStackReactQueryAPIs('4')
+
+    expect(apis).toEqual(['-'])
+  })
+
+  it('should throw error for missing version', () => {
+    expect(() => getTanStackReactQueryAPIs('')).toThrow('@tanstack/react-query version is required')
+  })
 })
 
 describe('loadModule', () => {