CommonJS to target ES2019 (#108)

* CommonJS to target ES2019

* Update PR number

Author: compulim

CHANGELOG.md

@@ -5,6 +5,14 @@ All notable changes to this project will be documented in this file.
 The format is based on [Keep a Changelog](https://keepachangelog.com/en/1.0.0/),
 and this project adheres to [Semantic Versioning](https://semver.org/spec/v2.0.0.html).
 
+## [Unreleased]
+
+### Changed
+
+- Changed ECMAScript target version, by [@compulim](https://github.com/compulim), in PR [#108](https://github.com/compulim/react-chain-of-responsibility/pull/108)
+   - CommonJS will target ES2019, changed from ESNext, will support Webpack 4
+   - ES Modules will continue to target ESNext
+
 ## [0.4.0] - 2025-10-22
 
 ### Added

packages/react-chain-of-responsibility/tsup.config.ts

@@ -1,15 +1,24 @@
-import { defineConfig } from 'tsup';
+import { defineConfig, type Options } from 'tsup';
+
+const BASE_CONFIG: Options = {
+  dts: true,
+  entry: {
+    'react-chain-of-responsibility': './src/index.ts',
+    'react-chain-of-responsibility.fluentUI': './src/index.fluentUI.ts',
+    'react-chain-of-responsibility.preview': './src/index.preview.ts'
+  },
+  sourcemap: true
+};
 
 export default defineConfig([
   {
-    dts: true,
-    entry: {
-      'react-chain-of-responsibility': './src/index.ts',
-      'react-chain-of-responsibility.fluentUI': './src/index.fluentUI.ts',
-      'react-chain-of-responsibility.preview': './src/index.preview.ts'
-    },
-    format: ['cjs', 'esm'],
-    sourcemap: true,
+    ...BASE_CONFIG,
+    format: ['esm'],
     target: 'esnext'
+  },
+  {
+    ...BASE_CONFIG,
+    format: ['cjs'],
+    target: 'es2019'
   }
 ]);