diff --git a/.changeset/ssr-mock-canvas-client-rect.md b/.changeset/ssr-mock-canvas-client-rect.md
new file mode 100644
index 00000000..f3088c3e
--- /dev/null
+++ b/.changeset/ssr-mock-canvas-client-rect.md
@@ -0,0 +1,5 @@
+---
+"@playcanvas/react": patch
+---
+
+Fix import crash in DOM-less environments (SSR/SSG) with engine 2.20.0–2.20.4: the module-scope null application's mock canvas now stubs `getBoundingClientRect`, which the `GraphicsDevice` constructor probes in those engine versions.
diff --git a/packages/lib/src/gltf/index.ts b/packages/lib/src/gltf/index.ts
index 074a44d9..145b9f86 100644
--- a/packages/lib/src/gltf/index.ts
+++ b/packages/lib/src/gltf/index.ts
@@ -6,7 +6,7 @@ export type { GltfProps } from './components/Gltf.tsx';
 export { Modify } from './components/Modify.tsx';
 
 // Hooks
-export { useEntity } from './hooks/use-entity.ts';
+export { useEntity } from './hooks/use-entity.tsx';
 
 // Types
 export type {
diff --git a/packages/lib/src/utils/validation.node.test.ts b/packages/lib/src/utils/validation.node.test.ts
new file mode 100644
index 00000000..030f411e
--- /dev/null
+++ b/packages/lib/src/utils/validation.node.test.ts
@@ -0,0 +1,28 @@
+import { describe, it, expect } from 'vitest';
+
+/**
+ * Regression tests for https://github.com/playcanvas/react/issues/335
+ *
+ * `getNullApplication()` runs at module scope, so importing the package must
+ * succeed in a DOM-less Node process (SSR / static site generation). Engine
+ * 2.20.0–2.20.4 crashed at import time because the GraphicsDevice constructor
+ * called `getBoundingClientRect()` on the mock canvas.
+ *
+ * These tests run in a plain `node` environment (see vitest.config.ts) with no
+ * jsdom and no playcanvas mocks — the same conditions as an SSG build.
+ */
+describe('DOM-less import (SSR)', () => {
+  it('imports the package entry point without a DOM', async () => {
+    await expect(import('../index.ts')).resolves.toBeDefined();
+  });
+
+  it('mock canvas answers the engine\'s layout probe', async () => {
+    const { getNullApplication } = await import('./validation.ts');
+    const app = getNullApplication();
+
+    // The same call the GraphicsDevice constructor makes in engine 2.20.0+.
+    expect(() => app.graphicsDevice.updateClientRect()).not.toThrow();
+    expect(app.graphicsDevice.clientRect.width).toBe(0);
+    expect(app.graphicsDevice.clientRect.height).toBe(0);
+  });
+});
diff --git a/packages/lib/src/utils/validation.ts b/packages/lib/src/utils/validation.ts
index bceb55fc..4a1dc22f 100644
--- a/packages/lib/src/utils/validation.ts
+++ b/packages/lib/src/utils/validation.ts
@@ -549,7 +549,19 @@ export function createComponentDefinition<T, InstanceType>(
  * @returns A mock application that is used to render the application without a canvas.
  */
 export function getNullApplication() {
-    const mockCanvas = { id: 'pc-react-mock-canvas' };
+    const mockCanvas = {
+        id: 'pc-react-mock-canvas',
+        width: 0,
+        height: 0,
+        // Engine 2.20.0–2.20.4 calls getBoundingClientRect() unconditionally from
+        // the GraphicsDevice constructor; 2.21.0 made it optional again
+        // (https://github.com/playcanvas/engine/pull/9000). This module is evaluated
+        // during SSR/SSG where no DOM exists, so the mock must answer the probe
+        // itself to keep the whole peer range (^2.11.8) importable in Node.
+        getBoundingClientRect: () => ({
+            x: 0, y: 0, width: 0, height: 0, top: 0, right: 0, bottom: 0, left: 0
+        })
+    };
     // @ts-expect-error - Mock canvas is not a real canvas
     return new Application(mockCanvas, { graphicsDevice: new NullGraphicsDevice(mockCanvas) });
 }
diff --git a/packages/lib/vitest.config.ts b/packages/lib/vitest.config.ts
index ad0f6e31..b8a766f3 100644
--- a/packages/lib/vitest.config.ts
+++ b/packages/lib/vitest.config.ts
@@ -1,18 +1,15 @@
-import { defineConfig } from 'vitest/config';
+import { defineConfig, configDefaults } from 'vitest/config';
 import react from '@vitejs/plugin-react';
 
 export default defineConfig({
   plugins: [react()],
   test: {
-    environment: 'jsdom',
-    globals: true,
-    setupFiles: ['./test/setup.ts'],
-    include: ['src/**/*.test.{ts,tsx}'],
     coverage: {
       provider: 'v8',
       reporter: ['text', 'json', 'html'],
       exclude: [
         'test/**',
+        'src/**/*.test.ts',
         'src/**/*.test.tsx',
         'src/**/*.d.ts'
       ],
@@ -22,7 +19,29 @@ export default defineConfig({
         branches: 80,
         statements: 80
       }
-    }
-    ,
+    },
+    projects: [
+      {
+        extends: true,
+        test: {
+          name: 'jsdom',
+          environment: 'jsdom',
+          globals: true,
+          setupFiles: ['./test/setup.ts'],
+          include: ['src/**/*.test.{ts,tsx}'],
+          exclude: [...configDefaults.exclude, 'src/**/*.node.test.ts']
+        }
+      },
+      {
+        // SSR regression tests — a plain Node environment with no DOM and no
+        // playcanvas mocks, mirroring what SSG frameworks do at build time.
+        extends: true,
+        test: {
+          name: 'node',
+          environment: 'node',
+          include: ['src/**/*.node.test.ts']
+        }
+      }
+    ]
   }
-}); 
\ No newline at end of file
+});