diff --git a/rollup.config.mjs b/rollup.config.mjs
index 6cc70d0..3af9b2c 100644
--- a/rollup.config.mjs
+++ b/rollup.config.mjs
@@ -6,7 +6,6 @@ export default [
   {
     input: 'src/index.js',
     output: {
-      esModule: false,
       file: 'matrix.js',
       format: 'cjs',
       exports: 'named',
diff --git a/tools/build-esm-facade.mjs b/tools/build-esm-facade.mjs
index e004fd9..2b360bd 100644
--- a/tools/build-esm-facade.mjs
+++ b/tools/build-esm-facade.mjs
@@ -6,14 +6,14 @@ const exportNames = Object.keys(matrixBuild);
 
 const exports = exportNames.map((name) => {
   if (name === 'default') {
-    return `export default matrix.default;`;
+    return `export default matrix.default.Matrix ? matrix.default.Matrix : matrix.Matrix;`;
   }
   return `export const ${name} = matrix.${name};`;
 });
 
 await writeFile(
   new URL('../matrix.mjs', import.meta.url),
-  `import matrix from './matrix.js';
+  `import * as matrix from './matrix.js';
 
 ${exports.join('\n')}
 `,