diff --git a/build.js b/build.js
index e1ea648d..56e7c094 100644
--- a/build.js
+++ b/build.js
@@ -13,7 +13,6 @@ const defaultOptions = {
   sourcemap: true,
   treeShaking: true,
   target: browserslistToEsbuild(),
-  mainFields: ['module', 'main'],
   outbase: 'src'
 };
 
@@ -31,7 +30,6 @@ inputs.forEach((item) => {
     entryPoints: [item.src],
     format: 'esm',
     splitting: true,
-    // keepNames: true,
     outdir: './build/esm/',
     outExtension: { '.js': '.mjs' }
   }).catch(() => global.process.exit(1));