diff --git a/scripts/esbuild.js b/scripts/esbuild.js
index f2974cb..ea28cd6 100644
--- a/scripts/esbuild.js
+++ b/scripts/esbuild.js
@@ -3,6 +3,7 @@
 
 import { build } from "esbuild";
 import { nodeExternalsPlugin } from "esbuild-node-externals";
+import * as fs from "fs/promises";
 
 const baseConfig = {
     entryPoints: ["src/index.ts"],
@@ -11,7 +12,7 @@ const baseConfig = {
     bundle: true,
     minify: false,
     sourcemap: false,
-    legalComments: "linked",
+    legalComments: "none",
     plugins: [nodeExternalsPlugin()],
 };
 
@@ -27,5 +28,21 @@ const legacyConfig = {
     format: "cjs",
 };
 
-build(moduleConfig).catch(() => process.exit(1));
-build(legacyConfig).catch(() => process.exit(1));
+async function addCopyrightHeader(filename) {
+    const header = `// Copyright (c) Tribufu. All Rights Reserved.\n// SPDX-License-Identifier: MIT\n\n`;
+    const content = await fs.readFile(filename, 'utf-8');
+    await fs.writeFile(filename, header + content);
+};
+
+async function buildAndAddHeader(config) {
+    try {
+        await build(config);
+        await addCopyrightHeader(config.outfile);
+    } catch (error) {
+        console.error(error);
+        process.exit(1);
+    }
+};
+
+await buildAndAddHeader(moduleConfig);
+await buildAndAddHeader(legacyConfig);