mermaidAPI should target node

webpack.config.base.js

@@ -0,0 +1,31 @@
+import path from 'path'
+import nodeExternals from 'webpack-node-externals'
+
+export const webConfig = () => {
+  return {
+    target: 'web',
+    entry: {
+      mermaid: './src/mermaid.js'
+    },
+    externals: 'fs',
+    output: {
+      path: path.join(__dirname, './dist/'),
+      filename: '[name].js'
+    }
+  }
+}
+
+export const nodeConfig = () => {
+  return {
+    target: 'node',
+    entry: {
+      mermaidAPI: './src/mermaidAPI.js'
+    },
+    externals: [nodeExternals()],
+    output: {
+      path: path.join(__dirname, './dist/'),
+      filename: '[name].js',
+      libraryTarget: 'commonjs2'
+    }
+  }
+}