diff --git a/README.md b/README.md
index a13a651..998aa22 100644
--- a/README.md
+++ b/README.md
@@ -179,8 +179,11 @@ defineUnPDFConfig({
 
 const pdf = await readFile("./dummy.pdf");
 const buffer = new Uint8Array(pdf);
+const pageNumber = 1;
 
-const result = await renderPageAsImage(buffer, 1);
+const result = await renderPageAsImage(buffer, pageNumber, {
+  canvas: () => import("canvas"),
+});
 await writeFile("dummy-page-1.png", Buffer.from(result));
 ```
 
@@ -191,8 +194,9 @@ declare function renderPageAsImage(
   data: BinaryData | PDFDocumentProxy,
   pageNumber: number,
   options?: {
+    canvas?: () => Promise<typeof "canvas">;
     /** @default 1 */
-    scale?: number;
+    scale?: number
     width?: number;
     height?: number;
   },
diff --git a/src/image.ts b/src/image.ts
index d3c3e32..6af8f04 100644
--- a/src/image.ts
+++ b/src/image.ts
@@ -49,6 +49,7 @@ export async function renderPageAsImage(
   data: BinaryData | PDFDocumentProxy,
   pageNumber: number,
   options: {
+    canvas?: () => Promise<typeof import("canvas")>;
     /** @default 1 */
     scale?: number;
     width?: number;
@@ -78,7 +79,7 @@ export async function renderPageAsImage(
     viewport = page.getViewport({ scale: outputScale });
   }
 
-  const canvasFactory = await createIsomorphicCanvasFactory();
+  const canvasFactory = await createIsomorphicCanvasFactory(options.canvas);
   const ctx = canvasFactory.create(viewport.width, viewport.height);
 
   await page.render({
@@ -94,19 +95,10 @@ export async function renderPageAsImage(
   return await response.arrayBuffer();
 }
 
-async function createIsomorphicCanvasFactory() {
-  // eslint-disable-next-line @typescript-eslint/no-unused-vars
-  let _canvas: typeof import("canvas") | undefined;
-
-  if (isNode) {
-    try {
-      _canvas = await import("canvas");
-    } catch {
-      throw new Error(
-        'The "canvas" package is required when running in Node.js.',
-      );
-    }
-  }
+async function createIsomorphicCanvasFactory(
+  canvas?: () => Promise<typeof import("canvas")>,
+) {
+  const _canvas = await canvas?.();
 
   return {
     _createCanvas(width: number, height: number) {
@@ -116,8 +108,11 @@ async function createIsomorphicCanvasFactory() {
         canvas.height = height;
         return canvas;
       } else if (isNode) {
-        // eslint-disable-next-line @typescript-eslint/no-non-null-assertion
-        return _canvas!.createCanvas(width, height);
+        if (!_canvas) {
+          throw new Error('Failed to resolve "canvas" package.');
+        }
+
+        return _canvas.createCanvas(width, height);
       }
 
       throw new Error("Unsupported environment for canvas creation.");
diff --git a/test/index.test.ts b/test/index.test.ts
index b92d39e..a2d84ee 100644
--- a/test/index.test.ts
+++ b/test/index.test.ts
@@ -57,6 +57,7 @@ describe("unpdf", () => {
     const result = (await renderPageAsImage(
       await getPDF("image-sample.pdf"),
       1,
+      { canvas: () => import("canvas") },
     ))!;
     // await writeFile(
     //   new URL("image-sample.png", import.meta.url),